Model Engine Maker

Engines => Your Own Design => Topic started by: Brian Rupnow on May 06, 2020, 08:14:23 PM

Title: Stephenson's Rocket
Post by: Brian Rupnow on May 06, 2020, 08:14:23 PM
I am interested in Stephensons Rocket. I have watched a few Youtube videos of it and read a few articles on it. I am curious about the valving on the steam cylinders. The cylinder and steam-chest seem to be conventional, but there doesn't appear to be an eccentric driven from the "axle" driving the valve slider back and forth. There does appear to be a shaft setting parallel to the cylinder rod, and some action of the cylinder rod moving a slider back and forth on that parallel rod, and a swinging lever connected to the valve slider rod. Can anybody shed some light on this please.---Brian
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on May 06, 2020, 08:45:37 PM
A little more study shows that the parallel rods were the cross head guides. A separate connecting rod ran from the cross head down to the "crank" on the large front wheels. Still haven't seen how the steam valve is operated.
Title: Re: Stephenson's Rocket
Post by: Firebird on May 06, 2020, 09:02:50 PM
Hi Brian

I have this that might help

(https://i.imgur.com/g9vlm8z.jpg)

Cheers

Rich
Title: Re: Stephenson's Rocket
Post by: crueby on May 06, 2020, 09:11:16 PM
In Rich's drawing, note the handles on the levers going from the eccentric linkage up to the steam chest. On other engines of that period it was common to have manual overides on the valving for use in starting up.
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on May 06, 2020, 09:18:16 PM
Based on the bottom drawing, it appears that this engine did have eccentrics mounted to the axle to operate the valve slider in the steam chest. I haven't been able to see them in any other videos except one by Keith Appleton, and even then it's not terribly clear. So, it appears that the engine and valve system is very similar to my Cretors Popcorn engine, other than a different style of cross-head guide and the fact that the rod from the eccentric is routed thru a hand control. Does that sound right?
Title: Re: Stephenson's Rocket
Post by: crueby on May 06, 2020, 09:25:59 PM
Sounds right. Looks like they put a pivot on each of the levers connected to the diagonal rod. Seems like there would be plans out there somewhere, if not castings as well, for such a famous engine. I recall there was a reconstruction of the Rocket at the railroad museum in Pennsylvania, saw it when I first was down there for Cabin Fever. Will see if I have any photos... The museum may have plans.


EDIT: Nope - that engine was the John Bull, not the Rocket.  It was at the Henry Ford museum. You can zoom in on the photo here, it shows the valve rods in the lower right:

https://www.thehenryford.org/collections-and-research/digital-collections/artifact/33379
Title: Re: Stephenson's Rocket
Post by: Firebird on May 06, 2020, 09:31:32 PM
Hi Brian

Sent you a PM

Cheers

Rich
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on May 06, 2020, 09:38:49 PM
Having had great success with the Cretors Popcorn engine (thank you Stu Hart) It would be fairly simple to make working engines for Stephenson's Rocket. The only thing that thru me was the lack of information about the eccentrics. I'm all "engined out" right now, but I'm thinking ahead to when I may get bored from doing nothing again.
Title: Re: Stephenson's Rocket
Post by: crueby on May 06, 2020, 09:42:04 PM
Well, found two things - this book on Amazon of all places:
https://www.amazon.com/Stephensons-Rocket-Manual-onwards-Workshop/dp/1785210637
And our amazing contributor Julius did these plans!
https://modelengineeringwebsite.com/Rocket_display_model_1.html
https://modelengineeringwebsite.com/Rocket_2.html
https://modelengineeringwebsite.com/Rocket_3.html
https://modelengineeringwebsite.com/Rocket_4.html
https://modelengineeringwebsite.com/Rocket_5.html
https://modelengineeringwebsite.com/Rocket_6.html
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on May 06, 2020, 09:54:49 PM
I was fortunate enough to actually find a solid model of the "Rocket".  Unfortunately, whoever made this didn't model the valve gear. I see from a drawing that was sent to me that the rod from the eccentric connects to a reversing lever which has a second rod extending from it to the valve slider.
(https://imagizer.imageshack.com/v2/1600x1200q90/924/mV4PtK.jpg)
Title: Re: Stephenson's Rocket
Post by: Admiral_dk on May 06, 2020, 10:01:53 PM
Chris beat me to it .... and I only took one picture of the Rocket on display in Yorkshire last year  :-[
On my picture (too big) it's obvious that there is no excentrik on the wheels and the engine is different in appearance - picture from front right - where I can see a steam chest behind the cylinder and it's connected to the crosshead guide ....
The picture from the Henry Ford Museum shows two excentrics in the middle under the engine .... and that bit is in complete darkness on my picture.
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on May 06, 2020, 10:02:47 PM
I actually did see the excellent drawings by Julius, but if there is information in there about the eccentric and valve rods, I couldn't find it.
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on May 07, 2020, 12:06:11 AM
Interesting stuff. The 3D model I show in post #9 was made in some other 3D software than Solidworks. What that means is that I can import it into Solidworks, and I can measure it, but I can not change the scale nor manipulate any of the part files. Currently, the piston diameter measures 1.3" diameter and the front wheels measure 9 3/8" diameter. That is too large for my tastes, although some quick calculations show that if I scale it to 0.481% of it's current size, the pistons will be 5/8" diameter and the large front wheels will be 4 1/2" diameter. That gets closer to a size I could actually work with. I could make a decent, but more simplified model with working engines. I guess the best place to start would be making two model engines of the correct size. This of course means I would have to design the engines first, which wouldn't be a giant hurdle.
Title: Re: Stephenson's Rocket
Post by: Elam Works on May 07, 2020, 01:21:14 AM
I seem to recall reading somewhere (likely Model Engineer in the eighties or nineties) a study of the Rocket where it mentioned the remains showed several different iterations of valve gear, or valve gear actuation. Like many things it have been altered back in the day, and during subsequent restorations. So you might have a choice!

-Doug
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on May 07, 2020, 01:40:18 AM
Hi Doug--I've done a lot of "in depth" Googling the last couple of days, and your right. I have seen 4 or 5 different valve gear arrangements on this engine. I'm going to stick with something very close to the valve gear used on the Cretors Popcorn engine, because I have built three of them, they all work good, and the valve gear is simple.---Brian.
Title: Re: Stephenson's Rocket
Post by: crueby on May 07, 2020, 02:38:48 AM
Just don't get the plan sheets mixed up and stick a spark plug in!   :Jester:
Title: Re: Stephenson's Rocket
Post by: sbwhart on May 07, 2020, 07:02:59 AM
Hi Bryan

I'v actually seen the original rocket when it was on display at the Manchester Museum of Science and Industry, can't remember if I took any pictures, I'll have a look in my files  just in case I did. One thing I did notice was that both valves were controlled by one eccentric the right had valve was direct off the eccentric with the left operated from same eccentric via lay shaft and levers.

Having read a few book about George and Robert Stevenson I know that Rocket went through many changes and rebuilds even after the Rainhill trials as they were striving to develop and perfect the locomotives many of the lessons they learnt they incorporated in there later locomotives.

Stew
Title: Re: Stephenson's Rocket
Post by: Jasonb on May 07, 2020, 07:51:45 AM
Julius' drawings are for a display model so unlikely to be fully details. You can buy a set of plans from Sarik here in the UK for a working model.

The photos here show the valve rods and linkages quite well and you can see the eccentrics on one of the front views

https://www.stationroadsteam.com/maxwell-hemmens-3-12-inch-gauge-rocket-stock-code-3815/
Title: Re: Stephenson's Rocket
Post by: J.L. on May 07, 2020, 02:31:28 PM
Hi Brian,

I am sure you know about the Rocket model offered by Occre Models in Spain. It is probably far less sophisticated than the level of engineering you are discussing here. But it has an attractive appearance.

Quoting Occre advertising:

"In 1829 the Liverpool and Manchester Railway held the Rainhill Trials to find the best locomotive for their line.

The winner, from a field of five entries, was George Stephenson and his Rocket. This locomotive, which only weighed 4.2 tons, had a multi-tubular boiler, almost 6 ft long with a diameter of 3 ft 4 in, that was of great efficiency in terms of heat transfer. The pistons, in the cylinders, which were set at an inclined position, were coupled up to 4 ft 8 in diameter drive wheels, and she was capable of reaching speeds of up to 25 mph."


Cheers...John

Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on May 07, 2020, 02:36:42 PM
Thank you Jason for the link. Those pictures do show a lot of detail.  Hi Stu, nice to hear from you. John, I've read about the Rainhill trials. wish I could have been there.---Brian
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on May 07, 2020, 05:15:18 PM
This mornings work consisted of modeling the engine base. It doesn't look like a lot, but all of the math data is embedded in the solid models. This afternoon I will recreate the cylinder and valve body and fit it to the engine frame.
(https://imagizer.imageshack.com/v2/1600x1200q90/923/9q2pQj.jpg)
Title: Re: Stephenson's Rocket
Post by: rklopp on May 07, 2020, 09:41:15 PM
There is a great book, M.R. Bailey and J.P. Glithero, The Engineering and History of Rocket published by the [UK] National Railway Museum in 2000. It is an academic-level investigation with hundreds of references and exquisite drawings.
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on May 07, 2020, 09:52:56 PM
Thank you Rklopp---That clears up a lot of the mystery.---Brian
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on May 07, 2020, 11:52:37 PM
And as the day wears on, the components are beginning to get much simpler. More related to machining and silver soldering than a complex bunch of platework tig welded together.
(https://imagizer.imageshack.com/v2/1600x1200q90/924/RpFP25.jpg)
Title: Re: Stephenson's Rocket
Post by: crueby on May 08, 2020, 01:06:41 AM
There is a great book, M.R. Bailey and J.P. Glithero, The Engineering and History of Rocket published by the [UK] National Railway Museum in 2000. It is an academic-level investigation with hundreds of references and exquisite drawings.
And another book to order for my library! Looks like a good one.
Title: Re: Stephenson's Rocket
Post by: derekwarner on May 08, 2020, 01:59:29 AM
Hi Brian.......looking impressive, just one question........

I understand the Drawings depict the Z reinforcement beam in the base, however find it conflicts with tradition in design

We have a 3 1/2" gauge functional scale coal-fired model of the Rocket here in OZ.......masses of polished brass...it is an absolute gem

Derek  :cheers:
Title: Re: Stephenson's Rocket
Post by: Jasonb on May 08, 2020, 07:37:24 AM

I understand the Drawings depict the Z reinforcement beam in the base, however find it conflicts with tradition in design

If Brian is going to be making a rocket then I expect that it will simply become a horizontal member when fixed to the side of the chassis once the cylinder and cross head guide assembly is mounted at an angle, a handed pair will be needed.
Title: Re: Stephenson's Rocket
Post by: sco on May 08, 2020, 10:52:41 AM
This might be useful: http://www.thehistoryblog.com/archives/52773 (http://www.thehistoryblog.com/archives/52773)

Towards the bottom of the page is a fully rotatable and zoomable model of the Rocket generated from LIDAR scans.

Simon.
Title: Re: Stephenson's Rocket
Post by: crueby on May 08, 2020, 12:56:30 PM
This might be useful: http://www.thehistoryblog.com/archives/52773 (http://www.thehistoryblog.com/archives/52773)

Towards the bottom of the page is a fully rotatable and zoomable model of the Rocket generated from LIDAR scans.

Simon.
That is an amazing scan/model!
Title: Re: Stephenson's Rocket
Post by: tangler on May 08, 2020, 01:30:57 PM
There is a Haynes Owners' Workshop Manual for Stephenson's Rocket.  It's  a bit of a coffee table book but does include quite a few detail drawings from the Glithero book

[https://www.amazon.ca/Stephensons-Rocket-Manual-1829-onwards/dp/1785210637/ref=sr_1_3?keywords=stephenson+rocket&qid=1588940780&s=books&sr=1-3]

Stay well,
Rod
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on May 08, 2020, 01:43:42 PM
Thank you so much to all who sent me information on Stephenson's Rocket.----Brian
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on May 08, 2020, 03:51:00 PM
With a bit more design work, all of the multiple plate welded up brackets and cross-head support stands become individual machined pieces. This isn't finished yet, because I have to add the valve body, and it may fall exactly in the same place as those two big round shouldered cylinder mounts. this is something i will know about a bit later today.
(https://imagizer.imageshack.com/v2/1600x1200q90/923/8d83Yr.jpg)
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on May 08, 2020, 07:34:18 PM
So, this is what we end up with. The cylinder is 5/8" bore x 1 1/2" stroke. The green base everything is mounted to is a direct "scale down" of the original Rocket base. I have mounted the steam chest in the same location as the original Rocket steam chest, but for now I have the control rod coming out the opposite end of the steam chest. Everything is symmetrical, so it can be easily reversed.
(https://imagizer.imageshack.com/v2/1600x1200q90/922/uF1R2H.jpg)
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on May 09, 2020, 05:16:13 PM
This morning I designed the "opposite hand" engine and base, and about half of the simplified body. This afternoon I will probably finish the body design. My main interest of course is the engines.
(https://imagizer.imageshack.com/v2/1600x1200q90/924/7cYb50.jpg)
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on May 09, 2020, 07:28:08 PM
That's enough fun for today. Even though I have "super simplified" the body, there is still a lot of pieces to it. I have to add some axles and stay rods yet.
(https://imagizer.imageshack.com/v2/1600x1200q90/922/reD0nu.jpg)
Title: Re: Stephenson's Rocket
Post by: crueby on May 09, 2020, 07:43:14 PM
Brian, are you planning on making the full working machine, with functional boiler too? Do you know about what size yet? Following along!   :popcorn: :popcorn: :popcorn:
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on May 09, 2020, 07:55:55 PM
No Chris, I'm not. I'm tired of building i.c. engines right now, and I've hurt my back.  I wanted to set at my computer and design something with a steam engine on it. Of course it's not much fun building just an engine, and I've always admired the Rocket. It will be ran on air pressure. Even just building a simplified model this is going to take a fair bit of time. The engines will be 5/8" bore and 1 1/2" stroke.
(https://imagizer.imageshack.com/v2/1600x1200q90/922/rrktl0.jpg)
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on May 10, 2020, 07:46:12 PM
So that's it. The model of the Stephenson's Rocket is greatly simplified from the original steam driven unit, but it certainly looks enough like the original that it won't be mistaken for anything else. Even in it's very simplified form it still represents an awesome amount of work. This has provided me with some nice design time, and the engine packages should be a lot of fun to make.
(https://imagizer.imageshack.com/v2/1600x1200q90/924/Vyr0Vj.jpg)
Title: Re: Stephenson's Rocket
Post by: gbritnell on May 10, 2020, 08:32:58 PM
Hi Brian,
Just a question? With the steam chest located where it's at how are you going to connect the valve linkage to the crankshaft?
gbritnell
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on May 10, 2020, 09:11:06 PM
From what I have been able to find out, the eccentrics which operate the valves set inboard of the drive wheels and operate a set of levers on a cross shaft mounted below the boilers just behind the drive wheels. This cross shaft is extended and has a second set of levers attached to it which operate rods leading up to the steam chest. I haven't modeled that part of things yet, but I post on three different forums and someone sent me the information on how this works. I am not going to add the shaft and levers which would be controlled by the operator to give a "neutral' or "reverse". See posts #2 and #21 of this thread, and you will see the valve gear as sent to me by Firebird and R. Klopp
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on May 10, 2020, 09:21:26 PM
And on the lighter side of things---it snowed 4" here yesterday. This is most unusual, but two of my grandkids took advantage and sent a picture of the "May Snowman".
(https://imagizer.imageshack.com/v2/1600x1200q90/922/A8V6Up.jpg)
Title: Re: Stephenson's Rocket
Post by: gbritnell on May 11, 2020, 12:13:03 AM
A great picture of the Rocket locomotive in cutaway.
Title: Re: Stephenson's Rocket
Post by: gbritnell on May 11, 2020, 12:22:05 AM
If you watch the video through to the end he turns the engine on it's side and explains the valve gear mechanism.
3AXUSzQIEmM
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on May 11, 2020, 01:05:58 AM
Great minds think alike George---I was watching Keith Appleton's video when my wife called me away to watch 60 minutes. I'm back down in the bat cave now and see your posting. :cheers:
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on May 11, 2020, 09:53:23 PM
George asked me yesterday how I was going to operate the steam valve. I had it in my head but it took most of today to design it and lay it out. The eccentrics mounted on the drive axle operate levers attached to an intermediate cross shaft, which is supported below the boiler. That shaft has a second set of levers on it which connect to the linkage running up to the steam-chest. Again, this model will not have the sophisticated hand controls that the original Rocket had. I have removed the near side drive wheel in his model, so you can see what my plan is for operating the valve operating mechanisms. Note that I have not shown the support for the intermediate shaft in this model.
(https://imagizer.imageshack.com/v2/1600x1200q90/923/OiQu73.jpg)
Title: Re: Stephenson's Rocket
Post by: crueby on May 11, 2020, 10:13:22 PM
Will there be an intermediate cross shaft per side? One per eccentric?
Title: Re: Stephenson's Rocket
Post by: zeeprogrammer on May 11, 2020, 10:33:02 PM
Looking forward to this. I haven't said much but I enjoyed Thumper.

I'm back down in the bat cave now

Is that where all this business started?  ;D
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on May 11, 2020, 10:43:30 PM
Chris--The single shaft will go all the way across. The two cylinders will be 90 degrees out of phase to make the engine self starting. I think I will be able to put the right side and left side levers 90 degrees out of phase on the single shaft and have it work. i'm not 100% sure on that yet.
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on May 11, 2020, 10:48:47 PM
Hello Zee--most of my ideas start down in the "bat cave". I have a perfect set-up here. My engineering office , washroom, machine shop and "main garage" are all on on one floor. I have a door from my office that opens directly to outside. I never really stop thinking about machinery and mechanisms.----Been that way all my life.---Brian
Title: Re: Stephenson's Rocket
Post by: crueby on May 11, 2020, 11:37:43 PM
Chris--The single shaft will go all the way across. The two cylinders will be 90 degrees out of phase to make the engine self starting. I think I will be able to put the right side and left side levers 90 degrees out of phase on the single shaft and have it work. i'm not 100% sure on that yet.
I am doubtful, at some points one will be moving forward while the other is moving back.
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on May 12, 2020, 12:10:48 AM
Chris--It is quite possible that I may make the single shaft fixed to the engine and attach the two levers on each side together with a sleeve that rotates freely on the fixed shaft. That will give me basically two completely independent engines. It then becomes a simple task of "timing" the eccentrics relative to each other.
Title: Re: Stephenson's Rocket
Post by: crueby on May 12, 2020, 10:24:15 PM
My copy of the book The Engineering And History of the Rocket by Bailey and Glithero arrived in the mail today. Looks like a great source, off to start reading that in the comfy chair...
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on May 13, 2020, 01:31:33 AM
Other than the engine assemblies, this model is relatively simple. Mostly straightforward milling and turning---but---The wheels are going to be monsters. Since I won't be running my engine on a track, the wheels can be mostly made from aluminum---I think. Very much of the "character" of this model is the wheels with square spokes.  There is no easy way to make these wheels. They are going to have to be "built up" from components---an inner hub, an outer rim, and individual spokes. For the scale I am working with, 3/16" square spokes look about right. I've thought about this a fair bit, and this is my plan--so far. I know that I can buy 3/16" square steel keystock. (Not sure if I can get 3/16" square aluminum or not). If I cut all of the spokes to an exact length, and make a proper jig to hold them, I can turn one end of the spokes to be round. I can lathe turn the inner hub and using my rotary table on the mill, I can drill 12 blind 5/32" diameter holes equally spaced in the hub. I can turn the hub as shown, so that when the spokes are installed they have to all fit into the groove, which will keep them all parallel with the face of the wheel. I'm thinking that would be a Loctite job. It would be a wonderful thing if, when assembled, the outer ends of the spoke array would be perfectly concentric with the center of the hub, but in the real world that doesn't happen. Thus, the design of the outer rim which is most visible will have a "lip" that extends down over the end of the spokes to hide them. That way, I can design the outer end of the spokes to be about 0.010" short of contacting the inner rim surface, but they will rest against the lip. At his point I see a simple jig to maintain concentricity between the outer rim and the inner hub. IF I use steel keystock for the spokes, and a steel outer rim, then I can use my tig welder to attach the spokes to the outer rim and it won't show. I don't have the proper gas bottle to weld aluminum, and I have no experience with welding aluminum, but with steel spokes and rim, I could manage.
(https://imagizer.imageshack.com/v2/1600x1200q90/923/nL5osv.jpg)
Title: Re: Stephenson's Rocket
Post by: doubletop on May 13, 2020, 04:32:42 AM
Brian

Are you planning slip eccentrics so the engine can do forward and reverse? Here bits from my Northumbrian build from some years ago, another Stephensons loco.

https://www.homemodelenginemachinist.com/threads/small-locomotive-boiler-me-northumbrian.14718/ (https://www.homemodelenginemachinist.com/threads/small-locomotive-boiler-me-northumbrian.14718/)

(https://www.mediafire.com/convkey/d506/1rwsjxzighwms3y4g.jpg)

Valve rockers

(https://www.mediafire.com/convkey/9195/yspuee0la1afyvg4g.jpg)

Slip eccentric valve gear operating

nEDLqLKn7pA
Pete

Title: Re: Stephenson's Rocket
Post by: Jasonb on May 13, 2020, 07:34:23 AM
Brian you could mill the spokes out of a disc of 3/16" plate, add a hub and rim much like you do with flywheels, it's just rotary table work.
Title: Re: Stephenson's Rocket
Post by: doubletop on May 13, 2020, 08:08:17 AM
Brian you could mill the spokes out of a disc of 3/16" plate, add a hub and rim much like you do with flywheels, it's just rotary table work.

John 'Bogstandard' had posted a 'howto' on Madmodder but the images are now missing. However, some years ago I had downloaded it and put it into a .pdf. As the resource is now effectively unavailable I doubt if anybody will complain if I post it here.

The files are too big for adding as attachments here so links are to my Google Drive, so be quick as I may remove them at some point in the future

https://drive.google.com/open?id=19Et4LAY95csaxEPOO0XNT4OOAJ_vmucA (https://drive.google.com/open?id=19Et4LAY95csaxEPOO0XNT4OOAJ_vmucA)

https://drive.google.com/open?id=1odIQxWjm8yn-m_lS9z5KQ1a1a7sFHKZU (https://drive.google.com/open?id=1odIQxWjm8yn-m_lS9z5KQ1a1a7sFHKZU)

https://drive.google.com/open?id=1KJuG52I485W14kn4UuKfjvrFJBZekK_P (https://drive.google.com/open?id=1KJuG52I485W14kn4UuKfjvrFJBZekK_P)

Pete
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on May 13, 2020, 03:33:56 PM
Thank you for the information fellows. I do not plan on having a reverse capability. Otherwise, the Northumbrian has exactly the same valve gear layout as I plan on using. I thought of carving the spokes out on a disc, but the Rocket has 12 spokes and I think that would just be too much to carve from one disc.
Title: Re: Stephenson's Rocket
Post by: cnr6400 on May 13, 2020, 04:44:21 PM
I recall reading somewhere that the original Rocket had wooden front wheels and a ball and socket joint from one spoke to the connecting rod each side. Making wood wheels might be less difficult than metal ones.

Another thought if making metal ones - have a waterjet or laser cutting firm cut all the spokes and the hub and rim/felloes in one part, and add "washer" shaped parts to each side of it for rims and flanges and crank plate protrusions. Just food for thought. A few rivets through the stack and some Loctite could hold the laminations together.
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on May 13, 2020, 05:07:20 PM
Due to the fact that there will be a lot of work in the model of the Rocket, I will first build the engines and bases and mount them to a Test Stand. The test stand will mimic all of the attachment points and axle positions that will be on the finished Rocket model, but will be a lot less work. After I have ran the engines to my satisfaction in the test jig, I will go ahead with the actual model of the Rocket.
(https://imagizer.imageshack.com/v2/1600x1200q90/922/mzlvm5.jpg)
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on May 13, 2020, 05:12:54 PM
cnr6400--I had the flywheels for the rockerblock engine water jet cut, and although the finished product was very nice, it cost me $100.  I can do a lot machining/fiddling around for $100.
Title: Re: Stephenson's Rocket
Post by: awake on May 13, 2020, 08:23:32 PM
Looking forward to this. I haven't said much but I enjoyed Thumper.

I'm back down in the bat cave now

Is that where all this business started?  ;D

Zee, I can't speak for Brian, but a lot of my projects start with the statement, "I'm guano do such-and-such" - so "bat cave" seems appropriate.

:)
Title: Re: Stephenson's Rocket
Post by: crueby on May 14, 2020, 08:31:04 PM
I recall reading somewhere that the original Rocket had wooden front wheels and a ball and socket joint from one spoke to the connecting rod each side. Making wood wheels might be less difficult than metal ones.

Another thought if making metal ones - have a waterjet or laser cutting firm cut all the spokes and the hub and rim/felloes in one part, and add "washer" shaped parts to each side of it for rims and flanges and crank plate protrusions. Just food for thought. A few rivets through the stack and some Loctite could hold the laminations together.
I've been reading through the Bailey and Glithero book on the Rocket, and the larger drive wheels did have wood spokes and rims, with metal hubs and tires. The smaller rear wheels were swapped out very early on, so its not clear if they had wood spokes or not. They were swapped with cast iron wheels off of a mine cart since the axle and bearings were mismatched, and they needed a quick resolution before the trials.  As for the crank pin, that appears to have changed over the years as well, between being mounted on a long flat strap running between hub and rim, and in an elongated section of the hub. Fascinating book, still reading....
Title: Re: Stephenson's Rocket
Post by: marcel on May 15, 2020, 12:40:43 AM
https://collection.sciencemuseumgroup.org.uk/objects/co26970/sectioned-conjectural-model-of-rocket-steam-locomotive-model-steam-locomotive
Title: Re: Stephenson's Rocket
Post by: crueby on May 15, 2020, 12:53:10 AM
https://collection.sciencemuseumgroup.org.uk/objects/co26970/sectioned-conjectural-model-of-rocket-steam-locomotive-model-steam-locomotive (https://collection.sciencemuseumgroup.org.uk/objects/co26970/sectioned-conjectural-model-of-rocket-steam-locomotive-model-steam-locomotive)
Brilliant! The plan views are terrific, as is the model. Thanks!!!   :cheers:
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on May 15, 2020, 01:28:28 AM
Marcel---Thank you. I hadn't seen that before.---Brian
Title: Re: Stephenson's Rocket
Post by: crueby on May 15, 2020, 02:18:17 AM
Playing around on that site, if you click on the link towards the lower right corner of the page, "View  manifest in IIIF viewer", you can see all the images and plan sheets in full high resolution. Awesome detail. Looks like they have 8 of the 9 or 10 pages of the original plans that Stuart Turner did for that model.
Title: Re: Stephenson's Rocket
Post by: Jasonb on May 15, 2020, 07:26:31 AM
Chris, the way you are talking I can see a new project taking shape :LittleDevil:
Title: Re: Stephenson's Rocket
Post by: Jo on May 15, 2020, 08:16:14 AM
Playing around on that site, if you click on the link towards the lower right corner of the page, "View  manifest in IIIF viewer", you can see all the images and plan sheets in full high resolution. Awesome detail. Looks like they have 8 of the 9 or 10 pages of the original plans that Stuart Turner did for that model.

They used 64ths  :facepalm:

Jo
Title: Re: Stephenson's Rocket
Post by: crueby on May 15, 2020, 02:14:23 PM
Playing around on that site, if you click on the link towards the lower right corner of the page, "View  manifest in IIIF viewer", you can see all the images and plan sheets in full high resolution. Awesome detail. Looks like they have 8 of the 9 or 10 pages of the original plans that Stuart Turner did for that model.

They used 64ths  :facepalm:

Jo
If you only had one of those newfangled compooter thingies that could convert units...  ::)
Title: Re: Stephenson's Rocket
Post by: crueby on May 15, 2020, 02:15:20 PM
Chris, the way you are talking I can see a new project taking shape :LittleDevil:
Its a good bet that its on the list....
Title: Re: Stephenson's Rocket
Post by: Jasonb on May 15, 2020, 04:29:23 PM

They used 64ths  :facepalm:


That's because even if they had been able to get thousandths on their steel rules it would have been difficult to set their firm leg callipers to the divisions

Maybe you should invest in one of these Jo :thinking:
Title: Re: Stephenson's Rocket
Post by: Jo on May 15, 2020, 06:04:23 PM

They used 64ths  :facepalm:


That's because even if they had been able to get thousandths on their steel rules it would have been difficult to set their firm leg callipers to the divisions

Maybe you should invest in one of these Jo :thinking:

If I need to use dividers I use one of these Imperialist tools :-X

All of my calipers: dial, digital or vernier, are modern they have metric measurements available on them

Jo
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on May 16, 2020, 12:25:21 AM
chris--i thought about what you said in regards to both sets of levers operating off a common shaft, and decided to change it to this. I will in effect have two completely "stand alone" engines and the eliptical cams on the front axle will be offset 90 degrees.
(https://imagizer.imageshack.com/v2/1600x1200q90/923/LE6Y1y.jpg)
Title: Re: Stephenson's Rocket
Post by: crueby on May 16, 2020, 01:04:32 AM
I found a diagram in that book which shows details of the the shaft where the handles are. It was actually two shafts, one with a hollow end that slipped over the other. The Rocket had one eccentric per cylinder, and used a slip system with drive dogs for forward and reverse. It also mentioned that the reason the steam chests were under the cylinder on the original layout was to drain water better, since the boiler at first had no steam dome so it tended to siphon water from the boiler at times. They had a spring to hold the slide valve against the valve port face when stopped.
Title: Re: Stephenson's Rocket
Post by: Jasonb on May 16, 2020, 07:21:58 AM
The tube and shaft is quite common. also found on engines with Wolfe valve gear like my Easton & Anderson

(https://img.photobucket.com/albums/v156/jasonballamy/Engineering/EastonandAnderson/IMAG1330_zps5bfd86cf.jpg)
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on May 16, 2020, 11:19:36 PM
I'm getting close to making a start on the Stephenson's Rocket cylinders. I went to my metal suppliers this week and bought a 12" length of 1 1/4" square brass. This will give me enough material to make two cylinders and two steam chests.---and maybe 4 cylinder end caps but I'm not sure yet. There's going to be a bit of finagling, because this brass is 1 3/4" across the diagonals and the bore in my lathe spindle is only 1 1/2". I don't want to waste any of the brass, because that 12" length cost me $50. I will probably hold one end in my four jaw chuck and use a live center to support the outboard end. I can turn the outboard ends of both cylinders in one set up, but I can't bore the cylinders in the same set up, so I"ll have to think more about this.
(https://imagizer.imageshack.com/v2/1600x1200q90/923/xXiAuF.jpg)
Title: Re: Stephenson's Rocket
Post by: Jasonb on May 17, 2020, 07:41:01 AM
Can't you just saw off a piece just over length and then hold in the 4-jaw to face the end, turn OD of one end and also bore all at the same setting then just turn it around to do the non piston rod end which is not so critical?

This cylinder is a bit longer and larger diameter but easy enough to hold though I used a soldered on port face so turned more of the OD

(https://img.photobucket.com/albums/v156/jasonballamy/Engineering/Prestons%20Oscillator/20191220_191657_zps1intqkqm.jpg)

And this one is only 3/16" shorter

(https://img.photobucket.com/albums/v156/jasonballamy/Engineering/Muncaster/DSC01201_zpsldkqvt17.jpg)
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on May 17, 2020, 03:10:01 PM
Maybe, Jason. My original idea was to turn both cylinders and four end-caps in one set-up, but I may have to rethink that.---Brian
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on May 18, 2020, 05:00:42 PM
Now---If I've done this right, there should be two identical cylinders in there. It is set up so that each cylinder, when sawed from the square stock should be the right diameter and have a 1" long "spigot" attached to one end of each cylinder, to mount it in the three jaw chuck for boring. After the cylinder has been bored, the 1" stub length will be cut off and turned to give me four cylinder end caps.
(https://imagizer.imageshack.com/v2/1600x1200q90/922/j7OkXY.jpg)
Title: Re: Stephenson's Rocket
Post by: crueby on May 18, 2020, 06:08:38 PM
Nice gang turning - this is going to be a fun project for us to watch along with!
 :popcornsmall: :popcorn: :popcorn: :popcorn:   (me and the elves)
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on May 18, 2020, 07:56:24 PM
And now you know how I spent my Monday. Everything went very well, no drama. There is more machining yet to be done on the cylinder bodies, but not today.
(https://imagizer.imageshack.com/v2/1600x1200q90/922/dtYSBn.jpg)
Title: Re: Stephenson's Rocket
Post by: Mike Bondarczuk on May 18, 2020, 10:33:34 PM
Hi Brian,

Very smart and a novel approach to a common problem with stock material builds.

I watch your progress on your previous engines and am amazed at your speed and ingenuity.

Mike
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on May 18, 2020, 11:03:17 PM
Thanks Mike--I generally take a couple of weeks between builds, but with this damned virus there is absolutely nothing else to do.
Title: Re: Stephenson's Rocket
Post by: Art K on May 19, 2020, 12:14:41 AM
Brian,
I like your creative lathe dog. Looks great so far.
Art
Title: Re: Stephenson's Rocket
Post by: Craig DeShong on May 19, 2020, 02:04:52 AM
Following along Brian  :popcorn: :popcorn:

Thanks Mike--I generally take a couple of weeks between builds, but with this damned virus there is absolutely nothing else to do.

I知 with you there, I知 not looking forward to finishing the Witte, I値l need another project or I will go stark-raving-mad  :o

And actually, I may have a doozy in the works!

Title: Re: Stephenson's Rocket
Post by: crueby on May 19, 2020, 02:52:01 AM
Following along Brian  :popcorn: :popcorn:

Thanks Mike--I generally take a couple of weeks between builds, but with this damned virus there is absolutely nothing else to do.

I知 with you there, I知 not looking forward to finishing the Witte, I値l need another project or I will go stark-raving-mad  :o

And actually, I may have a doozy in the works!


Scale Dusenberg engine?
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on May 19, 2020, 05:25:58 PM
The outside of the rectangular areas of the cylinder have been machined this morning, all except for the radiused area. This was simple stuff, with the cylinders held in my milling machine vise. The rest of the things I have to do are mostly all rotary table work, so I need shafts mounted in each of the cylinders for my 3 jaw chuck on the rotary table to hold onto.  I could have made an expanding arbor to mount the cylinders on, but this works just as well. I cut a couple of 5/8" cold rolled steel shafts, long enough to stick out each end about 1", and Loctited the shafts into place. After all my machining is finished, a bit of heat applied to the cylinders and the shafts slide right out. If any loctite residue remains in the cylinder it will easily come out by running a 5/8"reamer thru.
(https://imagizer.imageshack.com/v2/1600x1200q90/924/T2vU3r.jpg)
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on May 20, 2020, 11:35:43 PM
Shopgeezer was asking how I machined the radius on the cylinder. This is a picture of my set-up. I'm end-milling with a 1/4" diameter endmill. The endmill is cranked down until it contacts the part and is locked there. The travel stops on the front of the mill are set to keep me from running the endmill into the larger diameter bands at each end of the cylinder. The mill bed travels in the X axis to the extent of the travel stops, then cranked back, and the rotary table is indexed about three degrees, then repeat---and repeat---and repeat. Eventually you will have milled all the way around to the next "flat" surface on the cylinder. It will need a bit of file and sandpaper cleanup, but it works very well.
(https://imagizer.imageshack.com/v2/1600x1200q90/923/6Hg63s.jpg)
(https://imagizer.imageshack.com/v2/1600x1200q90/923/Ehj7Cf.jpg)
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on May 21, 2020, 09:45:23 PM
I always consider it a huge success when I have to drill and tap 20 holes, drill 20 clearance holes, and all the parts fit together!!  Tomorrow I will probably work on steam chests.
(https://imagizer.imageshack.com/v2/1600x1200q90/923/cKWIWS.jpg)
Title: Re: Stephenson's Rocket
Post by: Craig DeShong on May 21, 2020, 10:51:08 PM
I知 with you there Brian.  Give me a one time difficult task, and I値l probably get it done without incident.  Give me a highly repetitive task, and the mind wanders and errors occur.  It痴 hard to maintain your concentration. Same reason why I never build the same model twice.  It would be 塗o, hum; boring, I致e done this before.

I have a friend in Ohio who builds engine models on commission.  He has built the same model a dozen or more times; sent his kids through college with the proceeds,  I would be bored mindless.
Title: Re: Stephenson's Rocket
Post by: awake on May 22, 2020, 01:25:29 AM
The outside of the rectangular areas of the cylinder have been machined this morning, all except for the radiused area. This was simple stuff, with the cylinders held in my milling machine vise. The rest of the things I have to do are mostly all rotary table work, so I need shafts mounted in each of the cylinders for my 3 jaw chuck on the rotary table to hold onto.  I could have made an expanding arbor to mount the cylinders on, but this works just as well. I cut a couple of 5/8" cold rolled steel shafts, long enough to stick out each end about 1", and Loctited the shafts into place. After all my machining is finished, a bit of heat applied to the cylinders and the shafts slide right out. If any loctite residue remains in the cylinder it will easily come out by running a 5/8"reamer thru.

Loctite on an auxiliary shaft has quickly become my go-to method for a number of machining tasks - especially when I need to ensure concentricity between the bore and the outside features, and/or have to do a number of different operations on each end of a part.
Title: Re: Stephenson's Rocket
Post by: crueby on May 22, 2020, 01:40:10 AM
Brian, you using the loctite 638 for the temp shafts? That version releases with heat like the Red does?  Hmmmm..... Another one for the box o tricks...!
Title: Re: Stephenson's Rocket
Post by: Jasonb on May 22, 2020, 07:26:58 AM
Even 648 the high temp version gives under moderate heating.
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on May 23, 2020, 04:24:11 PM
This morning I finished up the two steam chests. I had the outside machined yesterday, which involved 4 jaw set-up in my lathe to turn the round spigot. This morning I put the 4 holes in each corner and the cavity in the center. Once again the machining Gods smiled on me and everything bolts together!!
(https://imagizer.imageshack.com/v2/1600x1200q90/922/8PZFaH.jpg)
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on May 24, 2020, 06:16:55 PM
Today we have some steamchest covers and some pistons and piston rods. One noteworthy thing here---these small steam/air engines are not very forgiving of a non-concentric alignment between the pistons and piston rods. To get around that, I turn the pistons to 0.050" oversize, then screw the piston rod into the piston (they are both threaded #10-24) and coat the threads liberally with J.B. Weld.  After it sets up for 24 hours, I will grip the 3/16" diameter piston rod in my lathes 3 jaw chuck, and finish turning the pistons to the correct sliding fit into the cylinders.
(https://imagizer.imageshack.com/v2/1600x1200q90/922/gKCHdi.jpg)
Title: Re: Stephenson's Rocket
Post by: crueby on May 24, 2020, 06:18:45 PM
Excellent progress, watching along!
Title: Re: Stephenson's Rocket
Post by: Craig DeShong on May 24, 2020, 07:07:15 PM
... and finish turning the pistons to the correct sliding fit into the cylinders.


I致e been known to do that too :ThumbsUp:  great minds must think alike  :Lol: :embarassed:
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on May 25, 2020, 08:46:14 PM
Nothing real exciting today. I turned down the pistons to finished size and made up the two rod glands that prevent air escaping around the piston rod. While I had the cylinders disassembled I finished off the internal porting in each cylinder. I made up the two brass rod ends and screwed them onto the piston rods. I took a couple of 8-32 hex nuts and rethreaded them to 10-24 because they are a bit smaller and look better. That doesn't sound like much, but I used up most of my day doing it. I just got back from my "fat mans walk" and it is very warm outside.
(https://imagizer.imageshack.com/v2/1600x1200q90/923/oYwRfS.jpg)
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on May 26, 2020, 11:20:53 PM
I had the very best intentions today, of building the four brackets which support the cylinders.  However, "The best layed plans of mice and men Gang aft agley"---I did get the four pieces cut to size, and I actually did drill and tap four holes and add two counterbores and a bit of end profiling on one piece and got it mounted. That's not much to show for the day, but I promise---I'll get the other three finished tomorrow. Good wife and I were setting out on the back deck about 4:20 this afternoon having a vodka cooler, when suddenly it began to rain so hard we couldn't see the end of our yard and the wind was blowing so hard that my big oak trees were leaning almost horizontal. We quickly scurried inside and the wife wanted to know if we should head for the basement--She's been through a tornado before---I haven't. I said to wait for a minute and see what happens. Five minutes later the sun was shining again. Crazy, crazy day!!!
(https://imagizer.imageshack.com/v2/1600x1200q90/923/kaprf0.jpg)
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on May 27, 2020, 08:27:25 PM
So, as promised yesterday, today the aluminum feet were finished and bolted in place. The main baseplates for the right and left hand cylinder assemblies were cut to size and drilled to allow mounting of the cylinder assemblies. Tomorrow I will probably make the A shaped pieces that support the cross-head guides. I haven't cut the windows into the baseplates yet. Initially everything will be assembled "for fit" before I cut the windows.
(https://imagizer.imageshack.com/v2/1600x1200q90/923/r1KfHj.jpg)
Title: Re: Stephenson's Rocket
Post by: crueby on May 27, 2020, 08:43:30 PM
Rolling right along!   :popcorn: :popcorn: :popcorn:
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on May 29, 2020, 01:32:57 AM
Today was the day for cross-head guides and brackets. I don't really know why, but I had a horrible time with these brackets. I kept taking off a little bit here, and a little bit there, and by the time they all matched and looked right, I had almost used up my entire day. The 1/8" cold rolled steel guides themselves were easy enough, but the brackets almost kicked my butt!!
(https://imagizer.imageshack.com/v2/1600x1200q90/924/R9IhNI.jpg)
Title: Re: Stephenson's Rocket
Post by: Art K on May 29, 2020, 02:32:07 AM
Brian,
I think you nailed those brackets, so they didn't quite kick your butt.
Art
Title: Re: Stephenson's Rocket
Post by: stevehuckss396 on May 29, 2020, 04:12:37 PM
I'm really enjoying this one. Maybe because it's a loco. I'm a big train fan.
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on May 29, 2020, 04:46:35 PM
Good to have you watching Steve. I have seen some of your builds and admired your craftsmanship.---Brian
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on May 29, 2020, 09:50:57 PM
Today was cross-head day. I would rather run in circles and bite myself than make pieces this small, but these are probably the smallest parts of this build, and they turned out alright. Don't let the size of these parts fool you. To get them to slide freely on the cross head guides and not jamb up the cylinder over the full extent of it's stroke is almost a magic act. As you can see from the picture, I changed the design of the cross-head a little bit from my original plan which both made it simpler to build and let me use a store-bought shoulder bolt as the pivot. The round cross-head guides are silver soldered to the bracket closest to the cylinder. At the end farthest away from the cylinder they are just setting in reamed holes, which positions them accurately but lets me disassemble them if I need to.
(https://imagizer.imageshack.com/v2/1600x1200q90/923/R9SZoY.jpg)
Title: Re: Stephenson's Rocket
Post by: crueby on May 29, 2020, 10:39:45 PM
Coming together great, thats a lot of parts to align. No carb to build at least!
Title: Re: Stephenson's Rocket
Post by: stevehuckss396 on May 29, 2020, 11:20:05 PM
And no valve seats to lapp
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on May 30, 2020, 09:24:05 PM
Today was mostly given over to the sliding valves for each cylinder. They are finished and look all right, but I won't really know until I get my gaskets cut and installed and some air pressure to work with. I have been wondering for the last week how I was going to get air pressure into the rectangular "steam chest" that the slide valves set in. I decided today to scrap the aluminum steamchest covers that I made and replace them with mild steel. This will let me silver solder an air inlet tube to the center of each cover. The pressure doesn't care how it gets into the steamchest, as long as it gets in.
(https://imagizer.imageshack.com/v2/1600x1200q90/923/kHWOt1.jpg)
Title: Re: Stephenson's Rocket
Post by: crueby on May 30, 2020, 09:26:59 PM
Looking great!  I dont recall, do you already have the ports drilled through to the cylinder ends, and out to the exhaust?
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on May 30, 2020, 09:37:51 PM
Yes, the ports and exhaust are all drilled. I can't for the life of me remember how you persuade these things to run clockwise or counter clockwise.---It's been a long time since I built this style of engine. I think it's just how you set the timing/positioning of the eccentric??
Title: Re: Stephenson's Rocket
Post by: crueby on May 30, 2020, 09:53:01 PM
Yes, the ports and exhaust are all drilled. I can't for the life of me remember how you persuade these things to run clockwise or counter clockwise.---It's been a long time since I built this style of engine. I think it's just how you set the timing/positioning of the eccentric??
Exactly - if you put the eccentric 90 degrees to one side of the crank pin, it runs one direction, 90 degrees to opposite side, it runs the other way. Thats the 'nominal' 90 degrees, plus/minus whatever lead you design in. For a display runner, it doesn't matter a lot. If you have a reversing gear with two eccentrics, all it does is switch which eccentric is acting on the valve slider. Its amazing how many mechanisms were invented for reversing a steam engine, it would be a long list!
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on May 30, 2020, 11:06:10 PM
Thanks Chris.
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on May 31, 2020, 08:57:05 PM
Today was a minor milestone. I just finished making the gaskets for one of the two cylinders on this engine, and of course I wanted to see if /how it worked. I always get a little thrill out of reaching a point where the slide valve controls the movement of the cylinder.
gMx_5MBLW9w
Title: Re: Stephenson's Rocket
Post by: crueby on May 31, 2020, 09:29:51 PM
Can hear your grin in the video!   :ThumbsUp:
Title: Re: Stephenson's Rocket
Post by: Art K on May 31, 2020, 10:25:49 PM
Chris,
I think it was one of those ear to ear grins! Great job Brian!
Art
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on June 01, 2020, 09:52:02 PM
Some days you eat the bear---Some days the bear eats you!! I spent an absolutely insane amount of time today freeing up the cross head to slide smoothly with the extension and retraction of the cylinder. I got one unit finished. I can extend or retract the cylinder by shifting the slide valve and watching it smoothly do it's business.The other cylinder though, is being a beast and binding like crazy---and the slide valve isn't seating correctly against the side of the cylinder. If I can hear air hissing, then the slide valve isn't seating properly. I will fix the second unit tomorrow---and ---guess what?--I can't really do any more until I build the test stand to mount the cylinders and cross heads and baseplate to. After I get the test stand built, I will move on to the eccentrics and connecting rods.
(https://imagizer.imageshack.com/v2/1600x1200q90/922/H10L4b.jpg)
Title: Re: Stephenson's Rocket
Post by: crueby on June 01, 2020, 10:06:30 PM
By 'Test Stand', you mean the rest of the locomotive, right?   :Lol:
 :popcorn: :popcorn: :popcorn:
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on June 02, 2020, 12:13:41 AM
Nope---Due to the fact that there will be a lot of work in the model of the Rocket, I will first build the engines and bases and mount them to a Test Stand. The test stand will mimic all of the attachment points and axle positions that will be on the finished Rocket model, but will be a lot less work. After I have ran the engines to my satisfaction in the test jig, I will go ahead with the actual model of the Rocket.
(https://imagizer.imageshack.com/v2/1600x1200q90/922/mzlvm5.jpg)
Title: Re: Stephenson's Rocket
Post by: crueby on June 02, 2020, 12:37:13 AM
Slick setup!
Title: Re: Stephenson's Rocket
Post by: sid pileski on June 02, 2020, 01:54:22 AM
Brian- are you going to quarter the drive axle, I assume?

I notice in the model they are not.

Sid
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on June 02, 2020, 02:32:48 PM
the drive axle will be one piece.
Title: Re: Stephenson's Rocket
Post by: crueby on June 02, 2020, 02:36:33 PM
The crank pins should be 90 degrees offset from each other though, otherwise it wont self start.
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on June 02, 2020, 07:31:55 PM
I know that Chris, but thank you for the information. Always helps to have a second pair of eyes on a design.---Brian
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on June 03, 2020, 01:20:26 AM
I spent far too much of today getting the cylinder assemblies  to extend and retract when connected to the cross-head guides. In all honesty, I don't think I would recommend this style of cross head guide system. With the offset between the cylinder rod and the two cross-head guide rods, there is simply too much binding. I ended up having to o-ring one piston. My intent here was to use no o-rings, just a couple of oil retention grooves in the pistons. The best cross-head guide system I have seen is the one used on the Cretors Popcorn engine, where there is no offset involved. By the end of the day I had both cylinders extending and retracting while attached to the cross-head guides, but it was a hard fought battle.
Title: Re: Stephenson's Rocket
Post by: Jasonb on June 03, 2020, 07:41:43 AM
Usually the cross head is a lot longer so less likely to twist and lock up, take a look at the photo George posted on page 2 or 3 and you will see that it is about 3 times longer than yours.

It's quite common to have the guide off to one side, often in the form of a flat guide channel rather than a rod like you have, this sort of thing

(https://img.photobucket.com/albums/v156/jasonballamy/Engineering/Vertical%2024/DSC02754_zpsxbaejgpm.jpg)

But you can see that the guide part is a lot longer than the offset

Title: Re: Stephenson's Rocket
Post by: crueby on June 03, 2020, 01:37:42 PM
I found some pictures of the original Rockets crosshead in the Glithero book,. It had square cross section bars, each turned 45 degrees, with the crosshead bolting over in two pieces. Its crosshead was short, and showed severe wear from the twisting and rocking forces. As an early engine, they had not yet learned to make the crosshead longer to handle being offset.
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on June 03, 2020, 06:42:24 PM
Both cylinder assemblies mounted to cross bar of test fixture. I can't do any more now until I go and buy some material.
(https://imagizer.imageshack.com/v2/1600x1200q90/922/UffIG9.jpg)
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on June 04, 2020, 01:35:07 AM
Went across town to see my metal supplier and picked up a 1" thick offcut for $5.00 this afternoon. Brought it home and added it to the flat bar which supports the cylinders. I wear a mask my wife made from black cloth material, and every time I see myself in the mirror I think of the Lone Ranger. ---or some other masked desperado. Damn, I hate this covid stuff.
(https://imagizer.imageshack.com/v2/1600x1200q90/922/gpqQUn.jpg)
Title: Re: Stephenson's Rocket
Post by: crueby on June 04, 2020, 01:59:52 AM
The stand looks good, kemosabe!
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on June 05, 2020, 09:20:43 PM
The engine test stand is almost complete. About 95% of this stuff is "Pre-engineered" in my 3D cad work.--The other 5% is "make it up as I go along", then go back and update the model and drawings to reflect what I have really done. I have to make up a baseplate to add to the bottom of this stand, and then I'm about ready to begin all of the small pieces which are required to get power to that front "axle". You will notice that the front axle support has a weird shape. It is actually the drive axle support which goes on the train body itself, I just haven't cut the arc yet where it bolts to the underside of the boiler.
(https://imagizer.imageshack.com/v2/1600x1200q90/924/OFWxhf.jpg)
Title: Re: Stephenson's Rocket
Post by: steam guy willy on June 06, 2020, 04:11:38 PM
The stand looks good, kemosabe!

Hi Chris, Yea Kemosabe !!Takes me back 50 years to the 9" black and white  TV set !! ;D

Hi Brian. I also draw out stuff to make., but when I get in the WKSP what actually comes out depends on the tools and materials  the part emerges and then the drawing is modified !!  :popcorn: :popcorn: :popcorn:
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on June 06, 2020, 07:20:13 PM
The hole that my front axle sets in was drilled and then reamed to 3/8". When I put the axle in the hole, it was a terribly sloppy fit. I couldn't figure out why my reamer had cut oversize---it never did before. A closer examination this morning showed that I've been METRICED---the 3/8" reamer I had used was a 10 mm reamer, which is 0.394". Don't know what fool put the  metric reamer into the 3/8" reamer stand!!! Then I went to make the eccentrics which attach to the axle, and totally buggered them up. At that point I shut things down and took my good wife out for lunch, then had a walk and an ice cream cone. Now I will take another run at those eccentrics.---
Title: Re: Stephenson's Rocket
Post by: crueby on June 06, 2020, 08:11:14 PM
Uhoh, sounds like Jo sent over a shop elf to rearrange your tools. Bait a trap with some tea...
Title: Re: Stephenson's Rocket
Post by: Art K on June 07, 2020, 05:06:07 AM
 
Quote
Uhoh, sounds like Jo sent over a shop elf to rearrange your tools. Bait a trap with some tea...
:lolb: :ROFL:
Art
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on June 07, 2020, 09:59:17 PM
Words alone can not express how much work went into these eccentrics. I still need to make the eccentric retainer plate that bolts to one side of each eccentric to keep the eccentric straps in place, but I will save that for tomorrow.
(https://imagizer.imageshack.com/v2/1600x1200q90/922/ZtR29N.jpg)
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on June 08, 2020, 02:26:51 PM
This morning I got up and made the eccentric strap retaining plates (for the second time) and bolted them to the eccentrics. All looks good---I am going to turn a few thou off the heads of the #4 shcs to clear the shaft better (they are mounted to a dummy shaft in the picture).I'm not certain that it shows in the picture, but there is a #5 set screw in the hub area of each eccentric, which fixes them to the shaft.
(https://imagizer.imageshack.com/v2/1600x1200q90/924/TAXygv.jpg)
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on June 08, 2020, 09:30:55 PM
This picture shows the eccentrics with the eccentric strap retaining plates bolted on, setting in place on the drive axle. You can see the cut away portion of the axle mounting plate that is clearance for the eccentric strap as the axle rotates.  I went by Princess Auto today to buy some oilite bronze bushings to press into place in the axle mounting plate, but the people were lined up all the way around the building, keeping their 6 foot distance apart for Covid. I didn't bother stopping--I'll either make my own bushings or figure something else out.
(https://imagizer.imageshack.com/v2/1600x1200q90/924/vjNzma.jpg)
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on June 09, 2020, 10:39:31 PM
And today, I whittled out eccentric straps. Not difficult, but time consuming. There are actually two or three  ways to do eccentrics. The way I have done with two piece bolt together eccentrics and one piece eccentric straps, or you can do one piece eccentrics and two piece eccentric straps. I don't know which is easiest. I've made them both ways, and it ends up being about the same amount of work.
(https://imagizer.imageshack.com/v2/1600x1200q90/923/HNJdo5.jpg)
A5vFaNjReWc
Title: Re: Stephenson's Rocket
Post by: Admiral_dk on June 10, 2020, 11:51:21 AM
It's been mentioned many times by others, but it's usually the fidly bits that takes the longest times .... but you are making good progress none the less Brian.
Title: Re: Stephenson's Rocket
Post by: AlexS on June 10, 2020, 08:20:46 PM
Hello Brain,

I like the way you build it symmetric.
For making the eccentric, which turning tool did you use to cut (rough cut)? Didn't make a eccentric or one piece crankshaft before ;)

I also find this on the web. Something for the next project?  :stickpoke: :)

XmmutEViK7Y
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on June 10, 2020, 08:21:47 PM
This morning I put on my mask, stood in line, and bought four oilite bronze bushings that were 3/8" i.d. x 1/2" o.d. ---This afternoon I determined that there is no way in Hell that you can turn the outside diameter down to 7/16". Doesn't matter how sharp the cutting tool is, doesn't matter what speed you run the lathe at.--The bushings crumble before you can get them down to a 1/32" wall thickness. They were the only bushings available locally. Pooop!!!
Title: Re: Stephenson's Rocket
Post by: crueby on June 10, 2020, 09:01:07 PM
Never tried oilite, I have used bearing bronze, 932 or sometimes 660 I think, with good results. Its available in a number of diameter bars, cuts great.
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on June 10, 2020, 09:38:21 PM
Alex--The eccentrics were turned using brazed carbide tools. The brass eccentric straps were made from 3/8" brass plate. The center hole was drilled and reamed, the radii were drilled thru the plate, and the o.d. was rough sawn to shape on the bandsaw and then mounted on my rotary table to finish the o.d.
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on June 10, 2020, 10:03:02 PM
I have four little pivot arms for the eccentrics. They were laid out on a piece of brass plate, drilled, reamed, and rough cut on the bandsaw. On bigger pieces I generally go right from the bandsaw to my vertical belt sanding machine and finish them off "by eye". I can't do that on pieces this small, so they will be machine finished using my milling machine and rotary table. I will have to make up some simple fixturing to hold them, and will post pictures of "in process" work.
(https://imagizer.imageshack.com/v2/1600x1200q90/924/RBCLtk.jpg)
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on June 11, 2020, 04:21:23 PM
The pivot arms are completely finished (I think the wide ones get a slot added yet). These were too small for me to hand finish "by eye", so I made up a mandrel with a 7/16" diameter register on the end of it, over which the levers would fit (they are 7/16" reamed hole). The o.d. of the lever bodies is 11/16" diameter, the outside diameter of the fixture is 5/8". The flat head capscrew is 0.493" diameter, so it will not pass thru the bore on the brass bits. When the capscrew is cinched down tight, it captures the brass bit so it can not rotate. It is then a simple matter to hold the fixture in the 3 jaw chuck on my rotary table, set up the appropriate offsets, then turn the handle on the rotary table to spin the chuck around, while the endmill cuts with it's side to finish off the o.d. of the brass pieces.
(https://imagizer.imageshack.com/v2/1600x1200q90/924/oH3B0D.jpg)
(https://imagizer.imageshack.com/v2/1600x1200q90/923/gwZU98.jpg)
(https://imagizer.imageshack.com/v2/1600x1200q90/924/dBISEK.jpg)
(https://imagizer.imageshack.com/v2/1600x1200q90/923/SD88iX.jpg)
(https://imagizer.imageshack.com/v2/1600x1200q90/923/mlXgkE.jpg)
Title: Re: Stephenson's Rocket
Post by: steamboatmodel on June 11, 2020, 04:39:10 PM
This morning I put on my mask, stood in line, and bought four oilite bronze bushings that were 3/8" i.d. x 1/2" o.d. ---This afternoon I determined that there is no way in Hell that you can turn the outside diameter down to 7/16". Doesn't matter how sharp the cutting tool is, doesn't matter what speed you run the lathe at.--The bushings crumble before you can get them down to a 1/32" wall thickness. They were the only bushings available locally. Pooop!!!
Oilite bearing are made from a powder sintered in a mold and can not be machined, you are stuck with stock sizes.
Gerald. 
Title: Re: Stephenson's Rocket
Post by: Jasonb on June 11, 2020, 06:38:49 PM
They can be machined but the makers say very sharp tools, they don't like reaming as that closes up the pores. I have had no problem cutting with CCGT inserts though I did not go down to 1/32" wall which may have been too thing and what gave Brian problems though more likely low top rake on the brazed carbide tools he was using.

https://oilite.com/Best-Machining-Practices
Title: Re: Stephenson's Rocket
Post by: Elam Works on June 11, 2020, 07:54:22 PM
Yup, I have machined Oilite. Plenty of bushings and thrust washers where I needed a non-standard size. Sharp tool to avoid smearing, no problem. Usually use HSS rather than carbide so I can grind a sharper edge. Also, unlike regular bronze, positive rake rather than a neutral rake to help with shearing rather than plowing the material out of the way. Because the material tends to crumble and break up into small chips, you think it is turning great regardless of what the cutting edge is like. But check the surface with an eye lop to see if you are really cutting it or smearing it.

-Doug
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on June 11, 2020, 09:22:21 PM
Today we move a little farther towards a running engine. The eccentric pivot levers (for lack of a better thing to call them) are finished and in place on the engine. I still have to make up a few connecting links and rod ends, and figure out what to use for a flywheel, but it's getting close to "run time".
(https://imagizer.imageshack.com/v2/1600x1200q90/923/3DmBCZ.jpg)
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on June 13, 2020, 01:42:31 AM
I didn't work on the Rocket today. My "man chores" have been piling up for the last month while I played in my shop, so today was the day to --cut the lawn---fill in the hole that a groundhog tunneled under my patio stones and relay the stone---sweep up a terrible accumulation of swarf from my machine shop----clean up all of my outer garage---and put about a thousand tools away. I have been wondering just what I would use for a flywheel on these engines mounted on the test stand. When the engines are assembled to the train chassis, the big front wheels become the flywheels. However, I'm not ready to start making the wheels yet, and I didn't want to buy material to make a temporary flywheel from. Then I realized that I have been slowly pirating parts away from the original Rupnow Engine that I designed and built about 10 or 12 years ago, and that it had a pair of lovely brass flywheels that I can use.
(https://imagizer.imageshack.com/v2/1600x1200q90/924/kVF5HC.jpg)
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on June 14, 2020, 09:52:22 PM
The engine test stand has gained a footplate. It was getting top heavy and the foot plate gives me something I can attach to my desk-top to keep it from toppling over. All of the linkages have been completed and set roughly to the correct length. I have borrowed a flywheel from one of my early engines that is slowly being robbed of parts. I got tire of trying to source oilite bushings for the main drivewheel shaft, so machined some from brass and Loctited them in place. I have tested things to the point that when I turn the flywheel by hand the eccentrics operate the slide valves in the steam-chest which makes the cylinders extend and retract. They are still very stiff and "oinky", but I will chase down interferences and maybe put a 0.005" shim under one cylinder. Tomorrow I will machine the connecting rods and the piece they connect to at the drive axle.
(https://imagizer.imageshack.com/v2/1600x1200q90/922/chVfgm.jpg)
Title: Re: Stephenson's Rocket
Post by: crueby on June 14, 2020, 10:54:19 PM
Great progress, watching along (with the elves)...
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on June 15, 2020, 05:07:08 PM
Time to do my "Happy Dance"!!  First engine is up and running. The connecting rod is very crude and will be replaced by a much prettier one. Only the near side engine is hooked up at this point. I will now move forward and start setting up the far side engine.
Ii1sHQSQTBU
Title: Re: Stephenson's Rocket
Post by: Firebird on June 15, 2020, 05:44:23 PM
Hi Brian

 :ThumbsUp: :ThumbsUp: :ThumbsUp: :ThumbsUp: :praise2: :praise2: :praise2:

Cheers

Rich
Title: Re: Stephenson's Rocket
Post by: crueby on June 15, 2020, 07:16:46 PM
 :pinkelephant: :whoohoo: :pinkelephant: :whoohoo: :whoohoo:
Excellent!! Always fun to see it move the first time after so much work.   :ThumbsUp: :ThumbsUp:
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on June 15, 2020, 11:12:20 PM
I'm trying something I haven't done before. This is the connecting rod which goes to the flywheel on each engine. As designed (you can see it in the solid models) it is 0.350" diameter at the center with a 4 degree included taper out to each end, where it becomes flat. It is easy to do in CAD, considerably more difficult in real steel. The issue is that I am starting with cold rolled steel, and have never really found a way to machine cold rolled steel without leaving a lot of lines and ridges. I am machining with my top slide set over 2 degrees, so I can't use automatic feed, so it's hand crank all the way on both sides of center and use lots of cutting oil.That's okay, but there is a lot of sanding after the fact with #180 and #220 grit sanding strips. If I get the ends machined flat and cut to length, I think these rods will look quite elegant.
(https://imagizer.imageshack.com/v2/1600x1200q90/924/wHh1Hc.jpg)
Title: Re: Stephenson's Rocket
Post by: Jasonb on June 16, 2020, 07:13:57 AM
"hand Cranking" is possible where you are going wrong and using the handle can tend to lift and then lower the slide, you should be using both hands to on the rim of the handwheel to feed constantly.

The alternative is to do it between ctrs so you can use your auto feed, either offset the tailstock or put your boring head into the tailstock and use that to set the offset if you don't want to upset the tailstock position.
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on June 16, 2020, 11:10:38 PM
So now my engine(s) have two of the fanciest connecting rods that I've ever made. They turned out very nice, although there seemed to be a ton of work in them. The con rods were the last two pieces needed to make my engine set-up run. Now I have to spend time working out all the "stiffness" so I can get things to run on about 15 to 20 psi of air.
(https://imagizer.imageshack.com/v2/1600x1200q90/923/dwjgcE.jpg)
Title: Re: Stephenson's Rocket
Post by: gary.a.ayres on June 16, 2020, 11:11:58 PM
Looking great!
Title: Re: Stephenson's Rocket
Post by: Art K on June 16, 2020, 11:47:24 PM
Looks great Brian!
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on June 17, 2020, 01:18:39 AM
This afternoon I hooked up air to the second engine and it ran quite nicely. I have to go to the hardware store tomorrow and buy some very small gear clamps. I will make up a tee in the morning so one feed line can supply air to both engines. When the engines are ran independently, they are running on the strength of one piston only. When I run the two engines together, they will have the power of two pistons, so should require only half the air pressure I am currently using. As soon as I have both engines running together, I will oil everything up well and let them run for an hour. This initial run will get rid of any "stickiness" in the system.
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on June 17, 2020, 05:14:03 PM
Today is a banner day, with air supplied to both engines and both engines running together. I have made a video---please tell me if it works okay. Next step will be to start work on the chassis.----Brian
eHDop4lcIK4
Title: Re: Stephenson's Rocket
Post by: crueby on June 17, 2020, 05:24:32 PM
Excellent!!   :whoohoo:
Title: Re: Stephenson's Rocket
Post by: zeeprogrammer on June 17, 2020, 10:54:57 PM
Excellent!!   :whoohoo:

Ditto.  :ThumbsUp:

I may have lost my sense of time...but that sure seems like fast progress.
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on June 17, 2020, 11:33:30 PM
I spent a couple of hours chasing down "tight spots" in the system this afternoon. That is done basically by process of elimination.--Keep taking parts off one at a time until the main shaft rotates freely--open up clearances on the offending part, put it back on, then repeat. Eventually you get to a point where the main shaft rotates without any binding.--The result?---An engine set that runs consistently at 20 psi. There will be no more posts now, until I start fabricating the chassis which the engines bolt to.
CtDl6fQFLC4t=9s
Title: Re: Stephenson's Rocket
Post by: Art K on June 18, 2020, 02:58:00 AM
Runs great Brian!
Art
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on June 18, 2020, 06:11:08 PM
And here we have the rest of the material to build the chassis with.---Except for the big drive-wheels. If you are wondering, that's $97 worth of aluminum setting on the chair. I enjoyed a machining free morning. When I designed the chassis, I just thru in all the shapes with no real attention paid to how they all go together. This morning I started "finessing" all of the parts to add in the threads, bolt holes, etcetera.
(https://imagizer.imageshack.com/v2/1600x1200q90/922/mvBuSo.jpg)
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on June 18, 2020, 07:08:16 PM
Where to begin, Where to begin??? I think the simplest part is going to be the smoke-stack.---And no, I haven't got the faintest idea of how to make that frilly part that fits on top of the stack. I think to look right, I'm really going to have to make it, but I haven't got a clue as to how.
(https://imagizer.imageshack.com/v2/1600x1200q90/923/jFr4de.jpg)
Title: Re: Stephenson's Rocket
Post by: Jasonb on June 18, 2020, 08:18:57 PM
Unwrap it in your CAD program so it is flat sheet then print it out to use as a template then saw and file some sheet metal before rolling it back up and soldering into a ring.

Alternative would be to run a gig say 10dp gear cutter across the end of a bar at say 12 divisions then bore out the middle and bend what is left outwards to a trumpet shape.
Title: Re: Stephenson's Rocket
Post by: crueby on June 18, 2020, 09:06:24 PM
Unwrap it in your CAD program so it is flat sheet then print it out to use as a template then saw and file some sheet metal before rolling it back up and soldering into a ring.

Alternative would be to run a gig say 10dp gear cutter across the end of a bar at say 12 divisions then bore out the middle and bend what is left outwards to a trumpet shape.
Making it out of sheet and rolling it sounds like a great plan, probably how the original was done too, minus the cad design step!
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on June 18, 2020, 10:55:08 PM
And yes, my darlings--We have a smokestack!! Turned and drilled from 1 1/2" solid.  By the time I was finished the swarf in my tiny shop was knee deep.
(https://imagizer.imageshack.com/v2/1600x1200q90/923/VfLvtX.jpg)
Title: Re: Stephenson's Rocket
Post by: Art K on June 19, 2020, 12:05:36 AM
Yup, I can picture the knee deep swarf from here.
Art
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on June 19, 2020, 01:08:50 PM
This is where I am going now. An "exploded" view gives some pretty good insight of what lays ahead with the chassis build. the engine assemblies don't appear here.
(https://imagizer.imageshack.com/v2/1600x1200q90/922/zlpwI0.jpg)
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on June 19, 2020, 09:05:49 PM
Today's entertainment was end-plates for the boiler. There is nothing really special here, just a lot of machining. If you have a good eye you will see that one endplate only has two holes, as opposed to having three holes as shown in the exploded view. As I was about to drill the third hole in the second plate, I thought "Jeez, I'm not lifting elephants with this thing---2 holes will be enough." One endplate will support the smoke-stack and the other is bolted to the fire-box. The bolt heads will be on the inside where nobody will see them---so---clearance holes in the endplates, threads in the fire-box and smoke-stack support. You will also see that the design evolves as I make the parts. The end plates in the model were a lot of mass for no good reason. I relieved a lot of the center of each endplate, and then went in and modified the drawings.
(https://imagizer.imageshack.com/v2/1600x1200q90/922/SocwHk.jpg)
(https://imagizer.imageshack.com/v2/1600x1200q90/922/tz3Yrk.jpg)
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on June 20, 2020, 05:59:23 PM
This morning yielded a fire box. I decided to carve out most of the interior to make it a lot lighter, and I made it round so I can fit a nice fire box door. The only problem with buying off-cuts at my metal supplier is that sometimes trimming the off-cut down to the size needed to make the part is more work than making the part.
(https://imagizer.imageshack.com/v2/1600x1200q90/922/Vndtf1.jpg)
(https://imagizer.imageshack.com/v2/1600x1200q90/922/O5SiKy.jpg)
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on June 20, 2020, 08:27:50 PM
Does anyone know where I can buy this? I've seen them before but I can't remember where. They are basically a small diameter tube (or even solid would do) about 5/16" to 3/8" diameter formed into a continuous circle about 1 1/2" diameter. Model builders cut portions of them away from the circle to use as elbows in model piping.---Brian
(https://imagizer.imageshack.com/v2/1600x1200q90/923/3eMZKs.jpg)
Title: Re: Stephenson's Rocket
Post by: Jasonb on June 20, 2020, 08:51:44 PM
"360 degree Mandrel bend donut"

though I have not seen them in the sizes you mention, usually bigger for exhaust fabrication etc

Not to hard to make solid ones yourself, either turn on the lathe  or wrap rod around a larger one like a spring, cut off one turn and then flatten.
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on June 20, 2020, 10:07:53 PM
thanks Jason---It was only while I was making the post that I thought "Huh---It is only for show--Probably I could make it from solid."
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on June 22, 2020, 08:50:47 PM
Today I finished the assembly of the front portion of the chassis , including the front plate itself, a 1/8" spacer, the crazy smokestack support and the smokestack. That smokestack support is a monster. It required three different fixtures to machine that part. I could have designed it simpler, but I wanted to attempt all of the fixturing. I will post the finished assembly and the three fixtures required to machine the support.---I got lucky with the third set-up and was able to use the front plate as the holding fixture for the third machining operation.
(https://imagizer.imageshack.com/v2/1600x1200q90/924/H2BQ1i.jpg)
(https://imagizer.imageshack.com/v2/1600x1200q90/923/1mUVKQ.jpg)
(https://imagizer.imageshack.com/v2/1600x1200q90/922/Ag7Le2.jpg)
(https://imagizer.imageshack.com/v2/1600x1200q90/923/5qaAFd.jpg)
Title: Re: Stephenson's Rocket
Post by: Craig DeShong on June 22, 2020, 10:55:01 PM
Excellent!!   :whoohoo:

I値l agree!  Well done. 
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on June 23, 2020, 11:56:31 PM
Today was a major lurch forward. I started with a 3 1/2" x 12" long piece of aluminum, turned half of it to 3 1/4" diameter, cut it in half, and counterbored both ends to receive the end caps. There is lots of exciting machining yet to come on that main cylindrical body. I had to quit half way thru the day and fabricate some brackets for a new flower box that my daughter was given, then jumped back into the shop to finish the main body so I could make a "mock-up".
(https://imagizer.imageshack.com/v2/1600x1200q90/924/XEsQIc.jpg)
(https://imagizer.imageshack.com/v2/1600x1200q90/924/OiQVFN.jpg)
Title: Re: Stephenson's Rocket
Post by: crueby on June 24, 2020, 12:07:00 AM
Boiler is taking shape, its a very distinctive shape. On the original, the right side of the firebox was lopsided, so the frame on that side had to be different than the left. So, if a part comes out a little off, you could say it faithful to the original!


 :popcorn:
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on June 24, 2020, 07:34:54 PM
I just finished adding the "wood cladding" to my boiler. I used a small (3/16") center drill and set it up to interfere with the boiler o.d.x about 0.020". Set the table stops up on the mill x axis, and rotated the rotary table 19 degrees between each linear cut. It turned out nice.
(https://imagizer.imageshack.com/v2/1600x1200q90/924/y0Dmq7.jpg)
Title: Re: Stephenson's Rocket
Post by: crueby on June 24, 2020, 08:51:37 PM
Nice trick, gotta remember that one!
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on June 25, 2020, 12:18:16 AM
This afternoon I put in locating counterbores and #10 threads in the "boiler" to accept the steam dome and the safety valve. I never knew until this afternoon how badly I sucked at freehanding a "dome". It turned out okay, but the finished result does not reflect the first two attempts. I am not tearing down the set-up on the mill, because the slots for the axles and pivot rods still have to be machined.
(https://imagizer.imageshack.com/v2/1600x1200q90/922/jAA8aO.jpg)
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on June 25, 2020, 10:52:30 PM
Today I finished the work on the milling machine, and was able to tear down my set-up. You will see in the picture the end of the motor-mount bar, which runs completely thru the boiler from side to side. I was able to drill and mill the slotted hole thru, but that of course left round ends on the slot. I drove across town and bought a 1/2" square file to make the ends of the slot rectangular. There was a HUGE amount of time required to make those rounded ends rectangular, and I have a new blister in the palm of my hand from filing. The main "boiler" is almost finished. The motor mount bar will be held in place by bolts which are hidden by the end cap on the boiler. My initial thought were to Loctite the boiler endplates in place, but I have figured out how to use a "thru-bolt" that is hidden inside the firebox and goes completely thru the boiler and is threaded into the endplate which sets at the front of the boiler. Tomorrow I will make the bracket which supports the rear axle and the pivot shaft for the eccentrics. Then it will be time to start transferring the engines from the test stand over to the actual chassis. The wheels will be left as the last thing to do.
(https://imagizer.imageshack.com/v2/1600x1200q90/922/CcEmHo.jpg)
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on June 26, 2020, 09:11:22 PM
I'm finished with the chassis of the Rocket, to the point where I have to start transferring engine parts from the test stand over to the Rocket. I ended up having to put rubber o-rings on both pistons. The machine is setting beside me as I type this, running on 10 psi. It still doesn't want to self start, and it should. May be a matter of how I have the timing set, or may be there is still some friction in the system that it has to work thru. It's getting rather exciting now. Tomorrow should see the engines moved, and then I have to start on those big drive wheels.
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on June 26, 2020, 09:49:44 PM
Okay, we're good now. After running the engine for half an hour, it self starts. A bit of explanation---I'm not using Viton rings, just plain old rubber Buna-N o-rings. These rings are fine because there are no high temperatures to contend with.--But---they have an amazing amount of "stiction" when first used in an engine. If you give the engine a few drops of oil in the cylinder and run it for half an hour, the "stiction" from the ring goes away. There was enough air getting past the un-ringed piston to prevent the engine from self starting. Now, with rings on both pistons and half an hour run time, there is no residual "stiction" and the engines self start fine. The crank throws are 90 degrees out of phase.
Title: Re: Stephenson's Rocket
Post by: crueby on June 26, 2020, 10:15:23 PM
Terrific, this is coming along great!   :ThumbsUp:
Title: Re: Stephenson's Rocket
Post by: stevehuckss396 on June 26, 2020, 10:26:27 PM
But where is the pictures or video???
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on June 26, 2020, 11:05:36 PM
The video I posted earlier of the engines running won't change any---Just the engines will be running slower. This is the threaded rod that holds all of the chassis together. It passes thru a clearance hole in the firebox and the rear "cap", thru a clearance hole in the "boiler" and threads into the front cap and smokestack mount. It will get shortened up and the nut will be hidden inside the fire-box. The next picture I post will be with all of the engine parts in place on the chassis.
(https://imagizer.imageshack.com/v2/1600x1200q90/924/TGJOQg.jpg)
Title: Re: Stephenson's Rocket
Post by: crueby on June 26, 2020, 11:17:12 PM
The threaded rod is sorta accurate, the real one had a number of rods inside to keep the endcaps from bulging. During testing they added more as they figured out how many were needed.
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on June 26, 2020, 11:20:53 PM
That just shows you that "Great minds think alike"----or----"Fools never differ."
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on June 27, 2020, 03:54:26 PM
Oh Wow---If I just had some wheels, I could almost go for a drive!! All of the engine parts bolted right up where they were supposed to go. I have a few simple cosmetic detail to figure out, but I'm happy with the way this is looking.
(https://imagizer.imageshack.com/v2/1600x1200q90/923/69AuG0.jpg)
Title: Re: Stephenson's Rocket
Post by: stevehuckss396 on June 27, 2020, 03:58:42 PM
This may have already been talked about but I cannot remember. Is this engine scaled so it can run on some commercial size track like the garden railway guys use?

Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on June 27, 2020, 05:49:19 PM
No, it isn't. Although everything is scaled "proportionally", it isn't sized to suit any specific track size.
Title: Re: Stephenson's Rocket
Post by: Art K on June 28, 2020, 02:01:03 AM
Brian,
The rocket looks great, ready for takeoff. You can use whatever track size you want, with an appropriate length air hose. I must admit, I half expected to see the door open with the threaded rod sticking out.
Art
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on June 28, 2020, 02:37:10 AM
Art--I'm setting here with everything assembled, trying to decide what to do next. There is an assembly of flat-bars that run parallel to the boiler and out in front of the engine from the rear of the driver platform. I have the material so I probably will build them next. I'm also thinking about how I am going to anchor the stay rods that act as braces on the smokestack and drivers platform. I would like to make them from 1/8" diameter aluminum round rods, but that creates a problem at the ends where they transition from round to flat. I might make them from 1/8" diameter steel cold rolled, which would let me silver solder a very small flat bar to each end. I checked to see what size socket head capscrew would work to attach them, but the only size that has a head diameter less than 1/8" is a number "0". That is almost smaller than I can comfortably work with.
Title: Re: Stephenson's Rocket
Post by: Jasonb on June 28, 2020, 01:34:00 PM
hammer the ends out flat so they become wider and then you can drill a larger hole.
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on June 28, 2020, 02:01:14 PM
Jason--I did think of that, but will have to buy a piece and try it to see if it will work. I would really like to stay with aluminum for the stay rods, but I don't know how well it "flattens".
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on June 28, 2020, 07:54:56 PM
I've started taking applications for "Train Driver". This guy showed up last night just after dark!!!--I also have a five year old grandson visiting for a couple of days. He should have a card like Paledin---"Have Toys--Will Travel".
(https://imagizer.imageshack.com/v2/1600x1200q90/923/h9k1oD.jpg)
Title: Re: Stephenson's Rocket
Post by: crueby on June 28, 2020, 08:05:09 PM
Looks like a dark ride!   :Lol:
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on June 28, 2020, 11:20:10 PM
I'm coming right down to the wire on this thing. All I have left to build before tackling the wheels are the bands which go around the boiler (Which will probably be cut from some aluminum tubing) and the piping below the boiler, and the fire-box door. Since the piping below the boiler is only for show and not for go, I think I can bend it up from round bar. I will make up a welding jig as shown in red, then heat the rod until it is cherry red and bend it around the posts in the jig.
(https://imagizer.imageshack.com/v2/1600x1200q90/924/gXeDLl.jpg)
(https://imagizer.imageshack.com/v2/1600x1200q90/922/u7gUlY.jpg)
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on June 29, 2020, 05:20:31 PM
This is the piping that runs below the boiler in it's first stage of development. A simple jig was made from scrap 1/2" plate and four 1/4" dowels mounted in it in the correct position. The "pipe" is designed with 1/8" inside radius at the bends, and the easiest way to achieve that is to bends the "pipe" around the 1/4" dowels. Of course the "pipe" is really 5/16" diameter cold rolled steel solid. It is going to require some more "finessing" before it is installed in place. It was heated to bright red in the bend areas with my oxy-acetylene torch and bent by hand.
(https://imagizer.imageshack.com/v2/1600x1200q90/923/8FSryb.jpg)
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on June 29, 2020, 09:51:00 PM
Hah!!!--even the old and ugly get lucky sometimes. I had to go by my metal supplier today, and he had a cut-off of aluminum tube just about exactly the side I needed for the rings on the outside of my boiler. A little boring on the inside, and a clean up pass on the outside, and I have a lovely set of rings for the outside of my boiler. They will eventually be loctited in position, and the one ring that sets between the engines is going to have to be cut, but I'm so much happier making the rings this way than trying to form them out of aluminum strips bent around a form.
(https://imagizer.imageshack.com/v2/1600x1200q90/923/tbfi4X.jpg)
(https://imagizer.imageshack.com/v2/1600x1200q90/922/qSjUTX.jpg)
Title: Re: Stephenson's Rocket
Post by: crueby on June 29, 2020, 10:00:03 PM
Really adds to the appearance, great!
Title: Re: Stephenson's Rocket
Post by: Art K on June 29, 2020, 11:25:12 PM
Brian,
Looks great with the rings on it. The Rocket is really coming along well.
Art
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on June 30, 2020, 01:00:07 AM
Thanks Art---Now, jumping back onto the project I started much earlier today. The piece has been removed from the jig, ends sawed off to correspond with the fire-box width, and a vertical section silver soldered on. The vertical piece has a hole drilled and counterbored thru the center, and a #4 shcs will go thru it and screw into threads in the bottom of a hole in the boiler. Although I have never shown it in the solid models, I want the sawed off ends to have a flange where it meets the sides of the fire-box. I'll do that tomorrow morning.
(https://imagizer.imageshack.com/v2/1600x1200q90/922/d3IAY4.jpg)
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on June 30, 2020, 08:00:39 PM
Today I added the "flanges" to the piping which sets below the boiler, and I built what passes for a fire-box door. What a crazy lathe set-up to turn the tapered face on that "door". The only way I could make it work was to reach across center with the cutting tool and run the lathe in reverse. It worked fine, but was a really strange set-up.
(https://imagizer.imageshack.com/v2/1600x1200q90/923/SkS9wJ.jpg)
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on July 01, 2020, 01:45:06 AM
This afternoon, while I had everything disassembled, I decided to paint. I've been dithering for a month, trying to decide whether to paint this thing or not, but finally decided to go with more or less "traditional" colors. Semi gloss black on everything except the boiler and wheels, which will be "Knock your eyes out yellow". So I painted--cleaned up---found another part---painted--cleaned up--found another part. I went thru about 5 or 6 rounds of this before I had most of the black parts painted. Damn, there are a lot of parts!!! Haven't painted the boiler yet, because I haven't Loctited the boiler rings in place, but maybe tomorrow. The only thing left to fabricate are 6 "stay rods" of various lengths. I know the engines run, because they ran on the test stand.
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on July 01, 2020, 03:40:22 PM
This morning I Loctited the boiler rings in place. This isn't really a big deal on three of the rings. The fourth ring may be a challenge. It is split around the engine mounts, and split again on the bottom half below the motor mounts to clear the pivot support bar. If the Loctite doesn't want to hold on this ring I may have to "pin" the individual ring sections in place with 0.039" diameter pins inserted thru the ring sections and into corresponding drilled holes in the boiler body.  I wanted to paint the boiler today, but may have to put that off until tomorrow depending on how rapidly the Loctite sets up.
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on July 01, 2020, 09:23:14 PM
While I was walking today---I was thinking about stay rods. The smallest size socket head capscrew I carry is a #4, which has a 0.182" diameter head. If I spent a little time making up rod ends from 1/16" mild steel, then I can silver solder them to the ends of the stay rods. I think this is the best solution I have came up with yet, and since the stay rods will be painted black, I think it will work quite well, and give a good solid attachment between the stay rods and the rest of the machine.
(https://imagizer.imageshack.com/v2/1600x1200q90/922/LJn3Jm.jpg)
Title: Re: Stephenson's Rocket
Post by: crueby on July 01, 2020, 09:47:05 PM
Fun how ideas can come while doing something else - though you can look fun while frantically scrambling to find a pen/paper to write it down before forgetting it....  Not that I have done that.... today!   :ThumbsUp:
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on July 01, 2020, 10:30:56 PM
I try and think about "what comes next on my project" while on my "fat man walks". If I don't consciously make a decision to think about something specific, then I find myself counting footsteps. I feel like "the count" from Sesame street.
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on July 02, 2020, 01:38:20 AM
I think my bolted stay-rods are going to work out just great. They are (I think) the last parts to be fabricated, painted, and assembled before I start earning my living as a wheelright.
(https://imagizer.imageshack.com/v2/1600x1200q90/924/5ynvvy.jpg)
Title: Re: Stephenson's Rocket
Post by: crueby on July 02, 2020, 02:12:11 AM
Are you going to build the tender as well?


 :popcorn:
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on July 02, 2020, 11:19:28 PM
No, I'm not going to build the tender.---The shape of things to come---
(https://imagizer.imageshack.com/v2/1600x1200q90/924/boMrJR.jpg)
(https://imagizer.imageshack.com/v2/1600x1200q90/923/vmSEpN.jpg)
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on July 02, 2020, 11:51:39 PM
The driver is the fellow I put into all my production machine layouts for custom built machinery. Customers always want to see an operator shown at the correct scale. He is five foot nine inches tall and weighs 160 pounds. He is "North American Standard size." I didn't design him. Another engineer did, and I stole him from a set of engineering files years ago. My software package has the ability to scale him larger or smaller, but all the work I have ever done for customers is always done to "full scale". I had to calculate the scale I wanted to make my Stephenson's Rocket to and then scale Elvis to the correct size. He looks to be too small in relationship to the Rocket, but if you look at any You-tube videos of the rocket, the operators shoulders are about even with the top of the boiler. My cylinders are larger than "real scale" because this engine is going to run on air. Without the extra power gained from the "change of state from steam into liquid vapour" I was afraid that the cylinders running on air might not be strong enough, so I oversized them by about 30%.
(https://imagizer.imageshack.com/v2/1600x1200q90/922/bgpMjg.jpg)
Title: Re: Stephenson's Rocket
Post by: Art K on July 03, 2020, 03:47:43 AM
Brian,
Would that be Presley or Costello...Elvis that is. :lolb:
Art
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on July 03, 2020, 06:02:52 PM
I am a firm believer in welding fixtures. I find it impossible to hold things at a specific angle and rotation and expect them to stay in place while being silver soldered.  This shows  firstly, a two part welding fixture for attaching the stay rod to one of it's foot plates. The jig has to be two part so it can be disassembled to remove the part after it is silver soldered. The second fixture is a simple one piece jig for welding the second foot plate in place. There will be clean up after the welding is finished, and final shaping on the footplates to make them match the drawing.
(https://imagizer.imageshack.com/v2/1600x1200q90/924/mVrvZ1.jpg)
(https://imagizer.imageshack.com/v2/1600x1200q90/922/7PKMc2.jpg)
(https://imagizer.imageshack.com/v2/1600x1200q90/922/ShfdiH.jpg)
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on July 04, 2020, 07:47:45 PM
Slowly I'm getting closer to the end of the end. The short stay rods are finished, fitted, and painted. The only outstanding things to build now are the two stay rods that stabilize the tall smoke-stack. Then I will reassemble everything and get started on the wheels. I tried to buy material for the outer rim of the drive-wheels on Friday afternoon, but the man at the metal suppliers was way behind schedule, having been shut down on Wednesday for Canada Day. He told me he would check it out Monday and let me know if they have any extremely heavy wall tube. This is kind of a sucky picture, but black doesn't photograph terribly well.
(https://imagizer.imageshack.com/v2/1600x1200q90/923/0CdoH8.jpg)
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on July 05, 2020, 09:19:24 PM
Today all of the painted pieces were reassembled, with thankfully no major "gores" in the paint. That always seems to be an issue for me. The longest stay rods that help steady the smoke stack will be done tomorrow. Then I will jump head and shoulders into the wheelright business. Each drive wheel will be built up from 15 individual pieces, which include 12 spokes, a two piece inner hub, and a rim.---And yes Sparky, I will be using my tig welder for that.
(https://imagizer.imageshack.com/v2/1600x1200q90/924/igoQ1C.jpg)
(https://imagizer.imageshack.com/v2/1600x1200q90/924/wnPUfk.jpg)
(https://imagizer.imageshack.com/v2/1600x1200q90/922/bnS034.jpg)
(https://imagizer.imageshack.com/v2/1600x1200q90/924/9cbxUi.jpg)
Title: Re: Stephenson's Rocket
Post by: crueby on July 05, 2020, 09:23:58 PM
Looking great!  :popcorn: :popcorn: :popcorn:
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on July 06, 2020, 07:57:25 PM
TA-DA!!!--The last two stay rods are painted and installed. I'm just waiting for a call back from my metal supplier to confirm that he has the material I need for the outer rim of the two big drive wheels.
(https://imagizer.imageshack.com/v2/1600x1200q90/924/qFlK8p.jpg)
Title: Re: Stephenson's Rocket
Post by: gbritnell on July 06, 2020, 08:30:15 PM
Man o man that looks great Brian. Adding the paint to it really brought it alive.
gbritnell
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on July 06, 2020, 09:16:26 PM
Thanks George--It is really, really unusual for me to paint anything I build. I love the way this thing has turned out. I'm trying to get my steel supplier to get off their butt and get me a price on material to make the drive wheels. It means a lot to me to get a thumbs up from you.---Brian
Title: Re: Stephenson's Rocket
Post by: Art K on July 06, 2020, 11:23:14 PM
Brian,
I agree with George, the Rocket looks great with it's fresh coat of paint.
Art
Title: Re: Stephenson's Rocket
Post by: Firebird on July 07, 2020, 05:14:09 PM
Hi

Great build Brian  :ThumbsUp:

I have enjoyed following along

Cheers

Rich
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on July 07, 2020, 11:28:28 PM
Today I turned seventy four. Ringo Star and I share a birthday, but he is six years older than me. Happy birthday Ringo!! I spent the entire day setting up the engines to run in the newly painted chassis. One engine started up right away with no drama. The other engine was a stubborn pig all day, and I still don't have it running. I did pick up the material for the large drive wheels today, and I'm looking forward to starting on them as soon as I get the second engine to run.
Title: Re: Stephenson's Rocket
Post by: crueby on July 07, 2020, 11:38:25 PM
Happy birthday Brian!
Title: Re: Stephenson's Rocket
Post by: Art K on July 08, 2020, 12:01:30 AM
Brian,
Have a great Birthday! I Hope your wife cooks your favorite meal, and also your favorite cake.
Art
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on July 08, 2020, 12:41:37 AM
Well she got it very close Art.--Big barbecued steak and cheesecake for desert.
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on July 08, 2020, 02:16:34 AM
So, here we are kids!!! After what seemed to be an awful lot of frigging around, both engines are up and running on the model. To time these slide valve engines properly, the cylinder has to be either at full extend or full retract, and the valve control rod must be exactly at mid travel. That is not really as easy as it sounds.--A hint--put 3 setscrews at 120 degrees apart in each eccentric hub. Although that is not good practice on most hubs, if you don't do it, then when the engine is timed perfectly, the single set screw will be hidden behind something and you won't be able to access it. The engines are "lurching" a bit, but that is just a matter of timing, and can be corrected.
EkLAnVPH6nE
Title: Re: Stephenson's Rocket
Post by: Craig DeShong on July 08, 2020, 03:49:16 AM
Happy birthday Brian! 

The model runs and looks great too!
Title: Re: Stephenson's Rocket
Post by: Jasonb on July 08, 2020, 07:30:06 AM
To time these slide valve engines properly, the cylinder has to be either at full extend or full retract, and the valve control rod must be exactly at mid travel. .............................The engines are "lurching" a bit, but that is just a matter of timing, and can be corrected.

Brian, you actually want the valve to lead the crank which will give smooth running not have it 90 degrees, try about 20deg of lead on air and 30deg if on steam, exact angle will depend on any lap that you have on the valve.
Title: Re: Stephenson's Rocket
Post by: Mike Bondarczuk on July 08, 2020, 08:25:49 AM
Happy Birthday Brian  :cheers: and what a superbly designed and finished engine.
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on July 08, 2020, 08:26:45 PM
Thank you Jason--I will try that. Now I get to see whether or not I'd make a wheelright. This piece is 5 1/2" outside diameter x 3 1/2" inside diameter x 1.8" long. It is the only piece that size in all of Barrie, and I got it for $21.50 there is sufficient material there to make two drive-wheels, and I will try and make a detailed post as the drive wheel fabrication progresses.
(https://imagizer.imageshack.com/v2/1600x1200q90/922/n77kvX.jpg)
Title: Re: Stephenson's Rocket
Post by: crueby on July 08, 2020, 08:40:35 PM
Thats gotta be a heavy chunk too!  :popcorn: :popcorn: :popcorn:
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on July 08, 2020, 10:40:58 PM
I've looked at a few different ways of fabricating these large drive wheels. I really liked whats shown here, because the round holes in the hub locate the spokes radially, and the sides of the groove in which the spokes set keep the spokes all parallel.  The spokes could be loctited into the holes in the hub, and tig welded to the outer rim. The only problem is that every one of the 24 spokes would have to be set up in the 4 jaw chuck, indicated, and then turned down to 0.150" diameter in order to work. I don't mind a bit of 4 jaw set-up, but doing it repeatedly 24 times is a bit too much.
(https://imagizer.imageshack.com/v2/1600x1200q90/922/nVLkdz.jpg)
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on July 08, 2020, 11:09:21 PM
My current idea is a bit more exotic.--Has more parts, but is "easier?" to fabricate because I don't have to turn the ends of the square spokes to fit into round holes. I have reduced the number of spokes from 12 to 10, and they are all located by the machined red hub (the red hub is shown  both "in place" and copied to the right hand side of the assembly so you can see what it looks like by itself). The red hub, although it looks complex, is all just basic rotary table work using a 3/16" end-mill cutting 3/16" deep. The spokes can lay in their appropriate slots and be Loctited in place, and the outer ends of the spokes can be tig welded to the outer rim.
(https://imagizer.imageshack.com/v2/1600x1200q90/923/iW32c5.jpg)
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on July 08, 2020, 11:36:47 PM
Regardless of what I do with the inner hub and spokes, the outer rim will not change. Next step will be to mount the material for the outer rim on my lathe and machine two outer rims from it. Because of the very real possibility of heat distortion from welding changing things a bit, I will make the rim about 1/16" greater than the drawing calls for, and about 1/16" wider than the drawing calls for. This will allow me to make clean up passes after all of the welding is completed.
(https://imagizer.imageshack.com/v2/1600x1200q90/923/lLwFLz.jpg)
Title: Re: Stephenson's Rocket
Post by: BillTodd on July 09, 2020, 12:14:20 PM
Quote
I don't mind a bit of 4 jaw set-up, but doing it repeatedly 24 times is a bit too much.

Set up a square collet ?  or If you have one a small round ER collet will usually grab a square fairly well by the corners (in the spring relief cuts).
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on July 09, 2020, 01:17:03 PM
I don't have any collets of any kind. I may look into buying some.--thank you for the suggestion.
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on July 09, 2020, 02:02:49 PM
This hub seems to be the most complex part of the drive wheel assemblies. I was going to begin by machining the outer rims first, but I've had a change of heart, and this is what I will be making today.
(https://imagizer.imageshack.com/v2/1600x1200q90/923/nZzO4a.jpg)
Title: Re: Stephenson's Rocket
Post by: BillTodd on July 09, 2020, 02:32:16 PM

Harold Hall has this suggestion:

jEQDgFcFN1c
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on July 09, 2020, 03:14:54 PM
Here we have the hub, reamed to a 0.75" bore, and stock 1.25" o.d. mounted in the rotary table, and a slot 0.188" deep cut with a 3/16" endmill. One picture shows the cut slot, the second picture shows a piece of the 3/16" square key material tapped into place for a trial fit. I have found out two things. #1---My 3/16" endmill is painfully dull, and #2 that my shoulder wants to quit about half way thru taking 0.005" depth of cut. Next trick will be to index the rotary table 36 degrees and do it over again.
(https://imagizer.imageshack.com/v2/1600x1200q90/924/4Ws0Ch.jpg)
(https://imagizer.imageshack.com/v2/1600x1200q90/922/i8Z2jJ.jpg)
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on July 09, 2020, 04:05:37 PM
Things got a lot easier when I switched to a carbide endmill and was able to take 0.010" depth of cut. This is the hub which has not been cut to finished length yet, but has one spoke setting in place to show how it's going to work.
(https://imagizer.imageshack.com/v2/1600x1200q90/923/YOsJ3N.jpg)
Title: Re: Stephenson's Rocket
Post by: crueby on July 09, 2020, 04:28:13 PM
Should work out well, watching along....   :popcorn: :popcorn: :popcorn:
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on July 09, 2020, 08:13:19 PM
These shots show the two piece center hub and one spoke. I'm happy with it so far. It will require a bit of touch up with a file before final assembly, but so far--so good.
(https://imagizer.imageshack.com/v2/1600x1200q90/924/lhChCr.jpg)
(https://imagizer.imageshack.com/v2/1600x1200q90/923/ADDVg5.jpg)
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on July 10, 2020, 02:34:44 PM
Things are going to stop for a while now. My lathe quit working last night about 6:00 o'clock.  I was half way thru a cut, turning at 400 rpm with a 0.015" depth of cut , in automatic feed mode. The lathe just stopped. No grind, no clunk, just stopped dead as if the power supply had died. I have checked the fuses and that is really all I can check. I'm afraid I may have to take my lathe to BusyBee in Toronto and have their technicians fix whatever went wrong.
Title: Re: Stephenson's Rocket
Post by: tghs on July 10, 2020, 03:45:29 PM
fault light?,, I find many of these machines use cheap plug and spade connectors,, when my mill was faulting I replaced the power cord to machine connectors with better ones,, never a fault again,, I used to work for biotech company that provided machines that had to run,, service people would respond 24/7 to get the unit back up and running,, the phone in check list started with #1 have you checked all the electrical connectors and fuses,, # 2 go back and really check all the connectors and fuses, #3 did you use a meter?  one of techs drove 3 hours one way in the wee hours to change a fuse that was claimed to have been checked,, (the machines were provided with a very well stocked spare parts box) good luck..
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on July 10, 2020, 11:58:26 PM
It's amazing what one old guy can do when he has some plywood, some metal rollers, and a cherry-picker engine hoist. The lathe came out of my shop, thru my office, into the main garage and onto my truck. It is now in Concord where the Busy-Bee main Ontario center is. i just got home and eat supper.
Title: Re: Stephenson's Rocket
Post by: Art K on July 11, 2020, 04:11:48 AM
Brian,
I don't envy you your day, sounds busy. Loading up lathe and all. My last weekend ended up in a similar manner. Flicked on the computer on switch, heard a popping sound reminiscent of the power supply blowing on the previous computer. Talked to my nephew the resident computer expert... well that is if you consider a 3 hour drive away resident. he said try a new atx style power supply, if that works you're good if not it's the 3 hour drive to drop it off so he can fix it, again. At least I didn't need a cherry picker to lift the computer into my trunk, or boot if you are elsewhere in the world.
Art
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on July 16, 2020, 12:55:00 AM
Aarghhh Billy--I think there's a wheel in sight!!! Got my lathe troubles sorted and just finished the first outer rim. Lookin' good so far. Mighty scary stuff parting off at that diameter.
(https://imagizer.imageshack.com/v2/1600x1200q90/923/p2VLYv.jpg)
Title: Re: Stephenson's Rocket
Post by: gbritnell on July 16, 2020, 11:56:44 AM
Hi Brian,
So after all that sweating, worrying and wrangling what was the problem with the lathe?
curious minds want to know!
gbritnell
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on July 16, 2020, 03:27:45 PM
This is what was wrong with my lathe One picture is of the gear cover that sets on the end of my lathe to protect my fingers from the gears. Notice the bent bracket at the lower right corner of it. That bent bracket pushes on a switch which disables the electrics on the lathe if the guard is removed. I haven't had that cover off the lathe in more than a year. Somehow---Perhaps metal fatigue? the bracket bent far enough that it no longer pushed on the button, and consequently the lathe stopped right in the middle of a cut. The switch it presses on is right below the gears and is virtually impossible to see unless you stand on your head to look for it. When I left the lathe in Concord at Busy Bee, I told them that my rpm indicator only worked intermittently and please either fix it or replace it, as well as please fix whatever is wrong that I have no power to the lathe. They replaced the rpm indicator, scratched their heads a bit and then found that bending the bracket by hand fixed things so it pushed the button and restored power to the lathe. I either didn't know, or else forgot that switch was even there.They charged two hours labor and the price of the new readout. My bill came to $129. So, they treated me quite honestly I think. They could have told me it needed a new motor and charged me another couple of hundred dollars but they didn't.

(https://imagizer.imageshack.com/v2/1600x1200q90/924/Y6Ip0a.jpg)
(https://imagizer.imageshack.com/v2/1600x1200q90/922/HqxmBG.jpg)
Title: Re: Stephenson's Rocket
Post by: gbritnell on July 16, 2020, 03:49:00 PM
Hi Brian,
I'm glad to hear it was so simple and a relatively low cost fix.
Now, make chips!
gbritnell
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on July 17, 2020, 12:20:10 AM
Now it's time to get into some complex stuff. To assemble all of the wheel parts and keep them all correctly positioned in relationship to each other, we have to use a "jig".--Also called a "fixture". In each wheel there will be 13 parts. An inner hub to align the spokes, a centering hub which fits inside the inner hub to adapt it to the axle, 10 spokes, and an outer rim. My plan is to use J.B. Weld to attach the spokes to the inner hub, and to tig weld the spokes to the outer rim. I started out the day by buying a 5" square piece of 3/4" thick aluminum plate which was scribed corner to corner to locate the center, and then a 5/16" center drill was used to put a center "divot" into the plate. The plate was then mounted in my lathe 4 jaw chuck, centered, and a boss was turned that is an exact fit into the inside diameter of the outer wheel rim. Then a 3/4" hole was drilled and reamed thru the center, and a countersunk pocket was put in the center to locate on the outer diameter of the inner hub. The two pictures I have loaded show the fixture after turning operations were completed, and with the inner hub, outer rim, and one spoke set in place. The depth of the turnings was calculated to give .062" of "air" below the spoke, so that it only is supported by the outer rim and the inner hub. There will be more posts as the wheel is developed, but this is my starting point.
(https://imagizer.imageshack.com/v2/1600x1200q90/923/QtfF8F.jpg)
(https://imagizer.imageshack.com/v2/1600x1200q90/923/nVv9cT.jpg)
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on July 17, 2020, 03:34:38 PM
Here we have the first wheel assembled in the jig.--all the spokes were covered with J.B. weld at the inner ends, then slid into the slots in the inner hub. They were all tapped down into the correct position in the outer rim, and then the outside of the centering hub was coated with J.B. Weld and then it was inserted thru the center. A very healthy 3/8" bolt and nut squeezes everything together, and will be allowed to set up for 24 hours. I will then tig weld the outer ends of the spokes to the outer rim. The welds will be on the side of the wheel which faces in towards the center of the Rocket, so will not be visible when all is assembled
(https://imagizer.imageshack.com/v2/1600x1200q90/922/hpJdcx.jpg)
Title: Re: Stephenson's Rocket
Post by: rudydubya on July 17, 2020, 04:42:01 PM
Nice work, Brian.  Quietly following along.

Regards,
Rudy
Title: Re: Stephenson's Rocket
Post by: crueby on July 17, 2020, 07:48:15 PM
Great looking wheel, nice way to make it.
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on July 17, 2020, 11:33:57 PM
So, what do you do while you wait 24 hours for the J.B.Weld to set up on the wheel in the jig?--Well of course, you make the outer rims for the non driven wheels. Unlike their bigger brothers which were machined from a piece of very heavy wall tubing, these smaller wheels were made from a solid piece of 3" diameter steel. My largest metal drill is 1" diameter. The holes in these smaller rims are 1.943" diameter. Thats a lot of boring passes at 0.015" depth of cut. Tomorrow morning I will make the hubs for the smaller wheels.
(https://imagizer.imageshack.com/v2/1600x1200q90/923/Fohhk8.jpg)
Title: Re: Stephenson's Rocket
Post by: steamboatmodel on July 18, 2020, 12:55:40 AM
fault light?,, I find many of these machines use cheap plug and spade connectors,, when my mill was faulting I replaced the power cord to machine connectors with better ones,, never a fault again,, I used to work for biotech company that provided machines that had to run,, service people would respond 24/7 to get the unit back up and running,, the phone in check list started with #1 have you checked all the electrical connectors and fuses,, # 2 go back and really check all the connectors and fuses, #3 did you use a meter?  one of techs drove 3 hours one way in the wee hours to change a fuse that was claimed to have been checked,, (the machines were provided with a very well stocked spare parts box) good luck..
Did computer and network trouble shooting for a while 30years back. Had one client who had a branch office in Buffalo NY and tice drove from Toronto Ont. to there branch to find the unit unplugged the first time and a circuit barker blown the second. The last time I was down there they had laid the cable between units on top of a heat rad in the winter. My wife went down one time and spent 13 hours and discovered someone was typing a O letter instead of a 0 zero number.
Gerald.
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on July 18, 2020, 07:28:10 PM
This morning I completed the hubs for the two smaller non-driven wheels, and machined a fixture to hold everything in position for tig welding. I used up every inch of 1/8" square keystock I had to make spokes for the small wheel that is in the jig. If all goes well with the tig welding, I think these are going to be very nice wheels for the Rocket.
(https://imagizer.imageshack.com/v2/1600x1200q90/922/1L1fN4.jpg)
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on July 19, 2020, 04:34:52 PM
So, here we are with one big wheel and one little wheel welded. The wheels haven't been removed from their jigs yet. They look nasty/ugly, but remember, all of the brown smoky stuff is going to disappear. The side with the welds on it is going to face inwards, so very little of these welds are going to be visible. I will post another shot of the same wheels later today after I get them cleaned up. I used my new tig welder for this job, because it is the only welder I have that can deposit a small controlled puddle of weld where I want it.
(https://imagizer.imageshack.com/v2/1600x1200q90/923/AUpDFJ.jpg)
Title: Re: Stephenson's Rocket
Post by: stevehuckss396 on July 19, 2020, 05:00:49 PM
So is the plan to mount them on a spindle and take some very light cuts to true up the wheels.
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on July 19, 2020, 05:36:23 PM
Steve--Actually I planned on posting about that exact thing. No matter how much care is taken with the jigs and set-up, there will end up being visible "wobble" when the wheel is rotated on the center hole in the hub. This can be addressed by taking "truing cuts" from the outer edges and sides of the wheel as the wheel rotates if the wheel is supported on an "axle" which fits into the hole in the center of the hub.
 I was just in the process of doing that, when I had a thought. I would strongly recommend that anyone who sets out to build fabricated wheels like this, put a bore thru the hub center 1/16" less than what it will end up being. This lets you build a fixture which accommodates the smaller center hole. Then when the wheel is removed from the jig, set it up in the lathe so that the chuck is gripping the outer diameter of the wheel, and that it is rotating "true" with no visible wobble or run-out. Then re-bore the center hole in the hub to the correct size. That is much easier than trying to re-machine the outer diameter and sides of the wheel to make it run true.
Title: Re: Stephenson's Rocket
Post by: stevehuckss396 on July 19, 2020, 07:13:14 PM
Makes sense to me
Title: Re: Stephenson's Rocket
Post by: crueby on July 19, 2020, 07:30:49 PM
Great tip!
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on July 19, 2020, 07:53:23 PM
This is a "trial assembly" of the welded wheels fitted to the chassis. When I get some yellow paint on those wheels, it's going to look awesome!!!
(https://imagizer.imageshack.com/v2/1600x1200q90/922/aTbFII.jpg)
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on July 20, 2020, 06:38:45 PM
Three wheels done, one to do yet. The good side which faces out away from center looks fantastic. The inside of the wheels which face towards the center are ugly as Hell. This is one of the few times I wish I had a little sandblasting cabinet. After I finish the last wheel, I will have to make a decision whether to spend a bit more time on the inside faces of the wheels with a bit of body-fill, or maybe just clean them up with my Dremel tool and leave it at that. The tig welder is perfect for making tiny welds on the ends of the 1/8" square spokes where they connect to the hub and to the outer rim.
(https://imagizer.imageshack.com/v2/1600x1200q90/923/BOfvfE.jpg)
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on July 20, 2020, 09:15:54 PM
This is something I've wanted to check, but couldn't until I had the drive wheels machined and assembled. My computer shows me that I have about 1/16" clearance between the clevis on the center shaft and the outside of the wheels outer rim. The computer is like having an old friend who lies once in a while. You want to believe everything it says, but you feel a lot better after you've actually verified that it did tell the truth. Sure enough, there is clearance there. Not very much, but enough.  The lever is at its maximum travel here, and from where I show it, it only swings back in the other direction away from the wheel.
(https://imagizer.imageshack.com/v2/1600x1200q90/924/WOExLh.jpg)
Title: Re: Stephenson's Rocket
Post by: crueby on July 20, 2020, 09:25:20 PM
 :popcorn: :popcorn: :popcorn:
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on July 22, 2020, 11:44:02 PM
This is a view of the "Belly of the Beast". I've spent the entire day reassembling, adjusting, adding a bit of clearance here and there. Right now one engine runs and one doesn't.  Tomorrow I will try and get the second engine set up to run correctly. I'm down to the point where I am just about ready to paint the wheels, but not until I have everything adjusted properly. After the wheels are painted and reinstalled, I have to fabricate a prettier air supply.
(https://imagizer.imageshack.com/v2/1600x1200q90/923/YSFVp4.jpg)
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on July 23, 2020, 01:46:28 AM
TA-DA!!!--It is alive and running on both engines. It is standing on end right now, which gives me much better access to the eccentrics so that I can adjust the valve timing.
IAgPIhVRkek
Title: Re: Stephenson's Rocket
Post by: crueby on July 23, 2020, 01:53:26 AM
Excellent!!!   :whoohoo:
Title: Re: Stephenson's Rocket
Post by: Kim on July 23, 2020, 05:06:11 AM
Looks great, Brian!
Don't you love it when they run!  :cartwheel:

Kim
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on July 24, 2020, 09:22:24 PM
Today was wheel painting day. Very nice yellow from Tremclad, same as the boiler. Now I have to figure out the pressure line plumbing for the cylinders. That is not going to be a simple thing. I have something in mind, but  have to do some cad work now to see if it's going to be possible.
(https://imagizer.imageshack.com/v2/1600x1200q90/923/EMW5TT.jpg)
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on July 24, 2020, 11:34:56 PM
Things are going to get really strange in order to get air pressure into the cylinders and still have everything "look right". There is a bit of work in this, but it is almost the last work I have to do before remounting the wheels.
(https://imagizer.imageshack.com/v2/1600x1200q90/924/oX27i6.jpg)
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on July 26, 2020, 11:48:50 PM
Today I worked on the series of manifolds necessary to get air into the cylinders. This was one of the areas that wasn't pre-engineered. I wanted the airline to be attached at the back of the Rocket, under the center of where the operator stands. Since this part of the build was a "make it up as you go along" operation, it required that the operators platform and fire-box and rear stay rods had to be removed from the model to be worked on.  First, I drilled and reamed a 7/8" hole completely thru the firebox. Then I made up a 7/8" length of aluminum which fit flush from side to side. A 3/16" diameter hole was drilled full length thru this piece, and each end was counterbored for an o-ring seal, and drilled/tapped for four #4-40 socket head cap screws. A hole was cross drilled half way thru the piece on center, and threaded 3/8"-16. The piece now obscured the 1/4"-20 thread for the bolt which holds the fire-box cover in place, but with some artful head scratching and measuring, a #10-24 hole was drilled and tapped in the appropriate position to accept a #10-24 shcs. While I had everything set up in the mill to cut the 7/8" diameter holes, I also drilled and tapped one side of the fire-box for a #8-32 set screw to anchor the 7/8" aluminum round bar in position. Also, I drilled a 13/32" clearance hole up thru the operators platform and thru the bottom of the fire-box. This allowed me to use a 3/8" diameter piece of steel, threaded on one end , to screw into the threaded hole in the 7/8" cross-piece. I also drilled a 1/4" clearance hole thru the rear axle bracket, which allowed me to install a piece of 1/4" diameter steel round bar thru the bracket and into a hole prepared in the 3/8" piece of steel. Some of these holes were much easier to drill in the manifolds from each end, so after I had made a trial assembly to be sure everything fit, I liberally coated all of the connections with J.B.Weld and screwed/pushed everything together and inserted steel plugs into the open ends where I didn't want air to escape. The metal tubes which extend downward from the valve boxes on the cylinders will have a flange on the bottoms which bolt to the ends of the 7/8' round aluminum. Damn, it takes almost as long to explain what I did as it did to do it. Last job of the day was to update the drawing package  and add these new parts to the assemblies and make detail drawings of them.
(https://imagizer.imageshack.com/v2/1600x1200q90/924/i9zKAO.jpg)
(https://imagizer.imageshack.com/v2/1600x1200q90/923/Y8yrIZ.jpg)
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on July 28, 2020, 11:55:21 PM
Today, I have had my butt thoroughly and awesomely kicked by Mr. Stephenson. The goal was to get set up for fabricating the air pressure lines feeding the steam-chests. This picture shows where I am ultimately going. It has been a worrisome and eventful day, but I have one side set up. The bent copper tube gets silver soldered to the flange. It is a "slip fit" over the barb hanging down from the steam-chest cover, and will be sealed tight with J.B. Weld.---At least that is the plan at the moment. If I'm really forced to, I can use a flexible nylon line there, but I don't really want to. By the time I'm done here, I'm going to have to repaint the fire box.
(https://imagizer.imageshack.com/v2/1600x1200q90/924/Xh4bl0.jpg)
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on July 29, 2020, 10:30:54 PM
Mr. Stephenson and I got on much better today. I'm not 100 percent sure right now, but I think I've almost ran out of parts to make.
(https://imagizer.imageshack.com/v2/1600x1200q90/923/XsyQ71.jpg)
Title: Re: Stephenson's Rocket
Post by: crueby on July 29, 2020, 11:07:27 PM
Glad you guys are getting along again!  Looking terrific.
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on July 29, 2020, 11:55:19 PM
I really have to try and find a model "driver". I need a little man 5 1/2" to 6" tall to stand on the platform. I haven't got around to checking any of the toy stores yet.
Title: Re: Stephenson's Rocket
Post by: crueby on July 30, 2020, 01:02:05 AM
I really have to try and find a model "driver". I need a little man 5 1/2" to 6" tall to stand on the platform. I haven't got around to checking any of the toy stores yet.
One possible with period clothes:
http://www.doctorwhostore.com/doctor-who-new-series-12th-doctor-peter-capaldi-series-9-action-figure-character-options/

Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on July 30, 2020, 01:27:46 AM
I looked thru that site Chris, and there is one fellow in Victorian era top-hat, but the color isn't quite right. (I wanted black clothing and top hat.) It doesn't say anywhere what scale these figures are made to (1:12 being optimal) and doesn't give the height either. Thanks, Brian
Title: Re: Stephenson's Rocket
Post by: crueby on July 30, 2020, 02:16:03 AM
I looked thru that site Chris, and there is one fellow in Victorian era top-hat, but the color isn't quite right. (I wanted black clothing and top hat.) It doesn't say anywhere what scale these figures are made to (1:12 being optimal) and doesn't give the height either. Thanks, Brian
Picture of the box says 5.5 inch tall. And you could always paint the clothes. Probably best to find a toy shop and browse in person. Or learn to carve...   :hellno:
Title: Re: Stephenson's Rocket
Post by: Art K on July 30, 2020, 03:21:24 AM
Brian,
I'm glad to hear that you and Mr. Stephenson are getting along better today. What's this you're going to browse toy stores for shop elves? :mischief:
Art
Title: Re: Stephenson's Rocket
Post by: steamboatmodel on July 30, 2020, 04:55:44 PM
Brian try some of the second hand stores for figures, they are cheaper then the toy/Dall stores and don't mind a bit of paint to revive them.
Gerald.
Title: Re: Stephenson's Rocket
Post by: awake on July 30, 2020, 05:58:03 PM
One possible with period clothes:
http://www.doctorwhostore.com/doctor-who-new-series-12th-doctor-peter-capaldi-series-9-action-figure-character-options/

One problem with those figurines is that they must be installed using a sonic screwdriver ... and the inside of the cab has to be larger than the outside!
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on July 30, 2020, 10:45:47 PM
Jigs and fixtures---Fixtures and jigs. Some of the jigs I make are based on pure mathematical calculations. Some are "best guess". This one is a combination of both. If I have lived right, this may be the last on this engine. This is one of the times where I have had to tell myself "Try it and see if it works".  You will see that the silver solder has joined the bent tube and the flange, but has also wandered over and attached the socket head cap-screws. I expected this. Thats why there are only two capscrews holding each flange in place on the fixture. I will mill the heads off of the capscrews and cut away the angle which forms the welding jig, to free up the parts.
(https://imagizer.imageshack.com/v2/1600x1200q90/923/q1q2gJ.jpg)
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on July 31, 2020, 11:49:49 PM
So--How did it work? it worked out perfect!!! Both welded pieces slid into place on the engine. I had used a bit of crazy glue to secure rubber o-rings into the ends of the 7/8" diameter manifold that ran thru the fire box. I coated the short tubes which were welded to the steamchest covers with J.B. Weld, and slid the welded pipes with flanges into place with no trouble. The flanges lined up, and the bolt holes in the flanges lined up. I tightened the flange bolts on one of the tubes, and felt it suck down into place as the rubber o-ring compressed. Went to tighten the bolts thru the other flange, and noticed that the flange wasn't setting as flush as I would have liked with the side of the fire box. I thought "Oh well, the copper tube will flex enough to let me tighten the bolts".---Hah!!!--The copper tube didn't flex at all. The silver soldered joint let go on one side. Ah Poop!!! To get really good secure joints with J.B. Weld, it shouldn't be disturbed for 24 hours after mixing.  That was okay. I had a small patent drawing to prepare for an inventor, so I spent this afternoon doing some honest design work while the one good silver soldered pipe was setting up. Tomorrow I will undo the broken/silver soldered tube and flange and  resolder it. After reassembly, assuming all goes well, I will hand paint the tubes to match the fire box.
(https://imagizer.imageshack.com/v2/1600x1200q90/923/436wHA.jpg)
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on August 01, 2020, 04:42:36 PM
So--How do you silver solder one end of a tube without melting  or burning out the J.B.Weld on the other end? You wrap the end with the J.B. Weld in a piece of cloth, tie it with some string to prevent it from sagging away from the tube, then soak the rag in water. As long as you don't spend too much time silver soldering the other end, the wet rag prevents any heat transfer into the other end of the tube.
(https://imagizer.imageshack.com/v2/1600x1200q90/922/thAse7.jpg)
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on August 01, 2020, 06:36:13 PM
After some re-soldering, re-assembly, and some touch up painting, we arrive at time for the final? "Beauty Shot" and the video. I still hope to find a period dressed driver to mount on the drivers platform, and I hope I can make a video of it running on it's own power across my office floor.
(https://imagizer.imageshack.com/v2/1600x1200q90/924/1h8puq.jpg)
vT1KZ5-8fCw
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on August 01, 2020, 06:56:55 PM
--Measured inside the flanges on my wheels is 4.7". That would be the inside to inside dimension on rails for it to run on. It would actually take very little to change it to suit a 4 3/4" track. I will sell the drawings as .pdf files and include the solid models as .step files for $40 Canadian funds. I normally charge only $25 Canadian for my engine drawings, but this build is far more extensive than any engines I have designed and built.---Brian
Title: Re: Stephenson's Rocket
Post by: crueby on August 01, 2020, 07:50:44 PM
Very well done!  As the Brits might (or not) say, you should be quite Chuff-Chuffed by the results!
 :ThumbsUp: :ThumbsUp: :ThumbsUp:
Title: Re: Stephenson's Rocket
Post by: Charles Lamont on August 01, 2020, 11:57:02 PM
Nice job, Brian.
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on August 02, 2020, 12:13:30 AM
Thank you Chris and Charles. I'm glad to be finished. i'm happy that the end result turned out so well.---Brian
Title: Re: Stephenson's Rocket
Post by: d.williams on August 02, 2020, 03:15:05 AM
Just lovely! I thoroughly enjoyed following along.
Don
Title: Re: Stephenson's Rocket
Post by: Pete49 on August 02, 2020, 05:11:07 AM
Never doubted how good the finished product would going by your other models and how you do things.
Title: Re: Stephenson's Rocket
Post by: Craig DeShong on August 03, 2020, 01:15:27 AM
Looks great Brian, and runs great. 



You致e built this model from beginning to end while I致e been 素utzing around trying to get the Witte model to run.  Your time has been much more productive than mine.  Bravo!

 :cheers:
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on August 03, 2020, 01:40:50 AM
Looking back to my first post, I see that I started this project around the 07 of May. WoW!!--I've spent almost three months on this build.---and I've worked on it almost every day. That is a long time for me to spend on one model. I haven't done a lot of completely new stuff here, but I have certainly sharpened up a lot of skills that I never use very much. I checked my cad files today, and there are 70 drawings involved with building this. That sounds like a lot, but when you make a detail drawing of each individual part, plus all the assemblies and sub assemblies, it adds up very quickly. I still hope to find an operator and show the engine moving under it's own power, but the build is essentially finished. Thanks for looking.---Brian
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on August 03, 2020, 04:39:13 PM
I just sold my first plan set for this engine. Now comes the tedious part---Opening each of the 70 drawings in Solidworks, then resaving them as .pdf files which can be opened without any special software. I used to have a piece of software that would do this automatically, but it never worked very well. Now I have something to do for the next couple of days.
Title: Re: Stephenson's Rocket
Post by: ddmckee54 on August 03, 2020, 08:30:57 PM
Brian:

Have you checked the doll house miniatures websites?  Doll houses are normally 1:12 scale.  I found links to a couple of Victorian era families that included a "Dad" dressed in a black coat for about $45 USD.  There are sources in Canada too, if you live on THAT side of the border.  I would imagine that a top hat would also be available from somebody.

True you'd have to dispose of the rest of the family some how...  But if you couldn't find a relative willing to adopt them, nobody here is gonna tell anybody where the bodies are buried.

Don
Title: Re: Stephenson's Rocket
Post by: crueby on August 03, 2020, 08:56:31 PM
Brian:

Have you checked the doll house miniatures websites?  Doll houses are normally 1:12 scale.  I found links to a couple of Victorian era families that included a "Dad" dressed in a black coat for about $45 USD.  There are sources in Canada too, if you live on THAT side of the border.  I would imagine that a top hat would also be available from somebody.

True you'd have to dispose of the rest of the family some how...  But if you couldn't find a relative willing to adopt them, nobody here is gonna tell anybody where the bodies are buried.

Don
A shop elf serial killer.....
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on August 04, 2020, 12:10:03 AM
My local "Toys are us" store has pose-able wrestlers and soldiers in the scale I want for about $12 Canadian. They are very good, and I can pose the arms wherever I want to (He has to be able to hold onto a cross-bar that I will install so he doesn't fall off). I can turn a top hat from aluminum and paint it black. Only problem is that they are either naked from their wrestler trunks up, or they are wearing bulky armoured vests. Nobody in my house sews, so I can't just make a black waistcoat and dress the silly buggers. I might go up there tomorrow and have another look. I also made a discovery--the black paint I used on the Rocket is "low gloss" black. ---when it is applied from the spray can. If you spray some into a container and apply it with a small brush to "touch up" any areas, it dries with a glossy finish. I now have a shiny fire-box.
Title: Re: Stephenson's Rocket
Post by: Art K on August 04, 2020, 12:35:55 AM
Brian,
I cant go away for a weekend at a location that has no internet with out you finishing your latest project! looks great. Now all you need is a round track to run it on.
Art
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on August 04, 2020, 09:54:32 PM
I got a driver!! He's a little too tall, but he has positionable arms and a full beard. I'm probably going to section a bit out of his legs to shorten him up, build him a top hat, and paint his upper body to look like a frock coat. Should be fun.--It's been a long time since I played with dollies.
(https://imagizer.imageshack.com/img922/9158/s9rarp.jpg)
(https://imagizer.imageshack.com/img922/8748/GuxLdB.jpg)
Title: Re: Stephenson's Rocket
Post by: crueby on August 05, 2020, 01:06:30 AM
Looks more like Ahnold than Stephenson, but thats fixable.  :ThumbsUp:
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on August 05, 2020, 01:21:36 AM
Whatever his name was, it's now "Shorty". He was 7" tall. I just did a 1" section job by removing his knees. He isn't going to need to bend them while he's standing on the Rocket's platform.
(https://imagizer.imageshack.com/img922/4474/0mnQ7z.jpg)
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on August 05, 2020, 04:58:53 PM
It only took a little time to make a fairly decent top hat from aluminum. The issue is that shorty's head wasn't exactly round, which made it difficult to fit the top hat. The solution to that was to grind the top of Shorty's head off on my big belt sander, down to a point where the top hat fit quite dashingly. I will epoxy a #10 bolt into the top of Shorties head and put a blind #10-40 tapped hole into the underside of the top hat (it is actually solid), so that it doesn't blow off on any of his high-speed runs. I lay in bed last night thinking of clothing as opposed to a paint-job, and have decided that it would be very little work to make a cloth cloak. The fingers from a ladies cloth glove might be about the right size to provide coat sleeves for him.
(https://imagizer.imageshack.com/img923/6661/TGeYvD.jpg)
Title: Re: Stephenson's Rocket
Post by: tghs on August 05, 2020, 06:21:50 PM
a perfect steampunk hat (just think, we were all steampunk before steampunk was cool) I do think it needs a brass hat band
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on August 05, 2020, 06:32:12 PM
TGHS--Much as I am rather intrigued by steampunk, I'm going to try and keep this guy "period correct". I am going to paint the hat. I have a terrible problem with black---it doesn't photograph well at all. I haven't totally made up my mind about the color yet, and black is certainly appropriate to the era.  I will wait and see how things develop before settling on a color.---Brian
Title: Re: Stephenson's Rocket
Post by: RonGinger on August 05, 2020, 07:44:07 PM
Don't give upon the combat looking guys. One of the guys in my model boat club took one and used a dremel and small grinding wheels to remove all the backpack and amo belts. Then used bondo to fill joints and build up. He even made the guy a nifty sailor hat of bondo.
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on August 05, 2020, 09:30:16 PM
Ron--I'm just not that "crafty". I do quite well with machinery design and building, but when it comes to carving I'm not very good at it at all. I've got my operator. He used to be a wrestler, but he's being "born again" as a train operator. I've just done a search in Barrie for someone who will custom sew dolls clothing, but didn't find anybody. I'm fumbling my way thru this, and I'm relieved at not having to get up and start machining something every day.
Title: Re: Stephenson's Rocket
Post by: crueby on August 05, 2020, 09:55:11 PM
Love the hat - Shorty is probably rather cross with you for all the hole drilling and sanding though...   :Lol:

I have a Capt. Jack Sparrow figure in a RC rowboat, had to replace his arms with dowels and drill big holes in his body to lighten him up enough to keep the boat from capsizing, I think he had the same body as Shorty under the jacket. He was not amused. Though it was funny the one time at the reflecting pool in Carmel when his boat capsized, I blamed it on too much rum!  :DrinkPint:
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on August 05, 2020, 10:01:12 PM
I've just posted an add in the Barrie "buy and sell" looking for a seamstress to sew doll clothing. I'm supposed to get paid for a small "patent drawing" tomorrow, and if that actually happens the train driver could end up being better dressed than me!!!
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on August 05, 2020, 10:12:54 PM
Shorty got his legs back today. I drilled a 3/16" hole into his lower leg and his upper leg this morning, and used a 1" long metal dowel inserted into both sides with lots of 2 part epoxy. He is standing with a bit of a lean to one side right now, but I will fix that tomorrow with my belt sander. Shorty may get a "hot foot" out of the deal, but at least he will then be an "upright citizen"!!
(https://imagizer.imageshack.com/img924/8481/b1im8B.jpg)
Title: Re: Stephenson's Rocket
Post by: steamboatmodel on August 06, 2020, 01:50:04 AM
Brian, if you do not want to paint the hat black, quite a few of them were dark brown.
Sorry I can't help with sewing clothes for your driver Shorty.
Gerald.
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on August 07, 2020, 09:41:36 PM
One thing about my driver---He's "Devilishly handsome". I gave up on actual dolls clothing. Nobody in Barrie answered my add about sewing some clothes for him, so I decided to go with some Testers enamel which I bought at the hobby shop here in town. It looks like he will need a second coat to fully cover up his wrestlers trunks. I didn't want to go with black, because it simply doesn't show up on camera very well. I actually never thought of "devilish" until after I painted him. I bought a bit of black paint to redo his boots, and a bit of white paint to give him a white shirt. There is a fabric shop about 1/2 a mile from my place, and when I get all finished painting I'm going to buy a piece of matching red material and make him a cape.
(https://imagizer.imageshack.com/img924/6630/MemCIm.jpg)
Title: Re: Stephenson's Rocket
Post by: crueby on August 07, 2020, 11:06:40 PM
You could always name him Flip (comic years ago Flip Wilson used the line 'The Devil made me do it' in a lot of his routines) .



Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on August 10, 2020, 08:57:39 PM
So--We're done like dinner. The Stephenson's Rocket is finished, and the driver (who used to be a wrestler) has a top hat and cape, and a devilishly good paint job. My good wife sewed the cape for me this morning. A "grab bar" has been added to the engine to give my driver a place to hang onto, and you can't see it, but the bottom of his legs are drilled and tapped for #5 socket head capscrews that come up thru the platform----He's not going to fall off. This model will get the "Place of Honour" on one of my shelves.
After I make this post I'm going to (hopefully) make a video of the Rocket driving across my floor, and then I'm outa here!!!
(https://imagizer.imageshack.com/img922/4222/ctuEuU.jpg)
(https://imagizer.imageshack.com/img922/9963/lVFpGe.jpg)
(https://imagizer.imageshack.com/img922/4631/ycHA1o.jpg)
(https://imagizer.imageshack.com/img924/2481/UOTEM2.jpg)
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on August 10, 2020, 09:21:43 PM
Final Video of Stephenson's Rocket--Watch closely--It happens quickly!!!
UfiepJnJSk0
Title: Re: Stephenson's Rocket
Post by: crueby on August 10, 2020, 11:33:58 PM
Wonderful!   :cartwheel:
Title: Re: Stephenson's Rocket
Post by: Art K on August 10, 2020, 11:55:46 PM
Brian,
Its time for the happy dance! :cartwheel:
Art
Title: Re: Stephenson's Rocket
Post by: Brian Rupnow on August 11, 2020, 01:13:13 AM
Thanks Chris and art. I actually got to see something I hadn't experienced before with the Rocket. The crankshaft throws are 90 degrees apart. The engine will self start. The model is quite heavy. So---plug in the air, and start raising the pressure via the regulator until the engine starts. Then very rapidly turn the pressure back down. If you don't, the engine goes totally ape-$hit and starts spinning like crazy and slithering all over the floor. There is a huge difference between enough pressure to self start and the pressure for a rather leisurely speed as seen in the video.
Title: Re: Stephenson's Rocket
Post by: crueby on August 11, 2020, 01:54:00 AM
Something I have done on engines that behave that way is put a flow restrictor at the air hose connection. Simple way is to put a needle valve in, so it can be adjusted. Lets high pressure in for starting, but won't let enough volume through for high speed running. It got my beam engine so it will run very slow.
Title: Re: Stephenson's Rocket
Post by: Craig DeShong on August 11, 2020, 08:31:45 PM
Nice Brian, though I blinked and missed it the on the first view  :lolb:

Maybe make a slow-mo video?

We壇 love to see the drivers cape blowing in the slip stream!
Title: Re: Stephenson's Rocket
Post by: Jo on August 12, 2020, 05:14:20 AM
 8)

Look like you need to make a rolling road display stand Brian ;)

Jo