Model Engine Maker
Engines => From Plans => Topic started by: propforward on January 24, 2013, 02:35:22 AM
-
OK folks, here goes. This is my second engine build log. I have no idea how long this will take, so bear with me.
For my second engine, I have chosen Elmer number 14 - the wobble plate. Here is a drawing of it, taken from Elmers plans.
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/14_wobble.jpg)
I chose this engine, because it incorporates a valve mechanism - therefore increasing the number of moving parts and complexity compared to the wobbler I just built - but at the same time the mechanism is an ingeniously simple one. As you can see, the valve mechanism is a simple rod with a machined groove, that slides across the inlet and exhaust. The valve is actuated by a lever, which is driven by a simple angled plate on the crankshaft.
Now, I am posting this in the CNC section, because, well, I intend to use a CNC machine on this.
Here it is:
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_9578Medium.jpg)
I came by this when my company discarded it at the end of an R and D project. (it is perhaps fortunate that the person responsible for deciding what to do with the leftover gear happened to be yours truly, but I digress).
It's not a heavy duty machine, but I have hopes to use this for making fancy spoked flywheels at some point, so this will be a nice project to get familiar with it. I am going to use it to cut out and drill at least pilot holes in the two main side plates, and base plate.
But tonight I started with some more traditional work - to wit, the bronze bearings for the crankshaft.
The plans call for bronze - I think brass would be fine, but it just so happens I had a short piece of 1/2" dia bronze, so since I have never machined that before, I thought it would be a bit of fun. I used a regular knife type cutting tool, with brass type spindle speeds, and that seems to work well.
Here is the first cut, starting to turn down to 3/8 OD for the flange.
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_9579Medium.jpg)
Turned down to 5/16 for pressing into the frames, and with hole drilled and reamed:
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_9582Medium.jpg)
And after parting off and clean up:
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_9583Medium.jpg)
I was happy enough with it, so I made another one. This is a rotten old blurred photo, but I am not a photographer, so never mind.
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_9584Medium.jpg)
And that's it so far. Not much - but it's a start. Sometimes, you just have to pick an engine and a component, and start. Then you get into a groove and get going.
This bronze is funny soft stuff, looks like a very sharp tool is important. It burrs up very easily.
-
Nice start prop. That is one of my favorites of Elmers and is a good slow runner. Great choice for a second engine.
Bill
-
Thanks Bill. I wanted to try something that included a valve mechanism, without going super complex. This fits the bill very nicely.
Actually I just went and checked my old orders, that is a piece of leaded naval brass, apparently - not bronze. I ordered it in 2008. Damn my memory. :facepalm2:
I think it will work just fine though.
-
Was just checking out the plans for the #14 Prop. Looks like a fun engine all right.
I think you'll be ok with the naval brass too. Not such a big disaster if you have to replace them later anyway.
Cheers
Steve
-
It should be fine Prop...I think even brass would be ok, there isn't much stress on those bushings. For the benefit of those that may not be familiar with the engine, you may wish to post a picture or cut-away view showing how it works. Elmer was so good at coming up with different ways to actuate a valve mechanism. Maybe that's why i like this one so much.
Bill
-
Hi Prop,
It looks like an unusual and interesting engine to build. The brass bushes should be ok, it's not as if you are going to use the engine to drive a generator 24/7 ;). The bushes look like nice work, but I have just one reservation. It is good engineering practice to drill/bore holes before making the parts which fit into them. This is because holes are usually made with fixed size tools such as drills or reamers and the holes produced are not always exactly to size. By boring/drilling the holes first you can then make the bushes to fit.
This may not be a problem on this project but it is a thought to keep in mind for future ones. In volume production systems very careful 'limits and fits' are observed and quality control systems ensure that these are adhered to. This is not always possible in what is effectively a prototype workshop where parts are made to fit. An illuminating read is John 'Bogstandard's' paddleduck build notes here http://www.machinistblog.com/bogstandards-paddleduck-engine-plans/ (http://www.machinistblog.com/bogstandards-paddleduck-engine-plans/) - worth reading even if you don't intend to make one yourself.
But good progress so far, let's have lots of pictures and don't worry about them being a bit out of focus - it is still possible to see the quality of your work.
Best regards
Terry
-
For the benefit of those that may not be familiar with the engine, you may wish to post a picture or cut-away view showing how it works.
Good point. I added a diagram and short explanation in the first post.
-
It is good engineering practice to drill/bore holes before making the parts which fit into them.
Fair point Terry, thanks. I made this very mistake on the wobbler, and ended up having to remake the brass bearing for that because the first one was too loose in the hole. This time I have tried to leave these bearings to the correct dimension for pressing into the frame.
And if I have to remake them, well, that will highlight the truth of your words very much. But I certainly shall not make the piston until the cylinder assembly is complete.
-
I managed to get a little bit more time in the shop today, so I made some progress.
The first part of the day was just spent turning and facing brass, and better understanding tool grind details, spindle speeds and feeds, and how they relate to finish.
After a little practice / playing about, I decided to tackle the wobble plate and collar.
These are two simple parts - a 1" diameter disc, which sits at an angle on a simple brass collar. Per Elmers guidance, I made the plate first, and then made the collar to suit.
I had some 1 1/8 brass in stock, so I faced off and turned the OD first.
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_9586Medium.jpg)
With that done, I drilled the through hole.
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_9589Medium.jpg)
I didn't worry overly about what hole diameter I ended up with, since I knew I was going to turn the OD of the mating part to suit. All I mean there is that I did not feel the need to set up and bore the hole to a close tolerance.
I parted the disc off, and must say I was happy with the finish on side 1 (which I faced earlier).
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_9591Medium.jpg)
Oh dear - but not so happy with the finish of the parted side.
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_9592Medium.jpg)
I suspect that if I had ground a better relief angle on the parting tool, I could have parted it to the right width, and got a decent finish too. Lesson learned.
Anyway, I decided to try and save the part, since it was on the thick side. I made a simple expanding collet from a piece of leftover brass. It is simply a piece of brass, with a shoulder turned on it to match the ID of the disc. Then, I drilled through and tapped M6 (because that was the size of countersunk screw I had handy), then counterbored, and then countersunk the ID. I then cut (with a hacksaw - quick and easy, but it did the job) 2 slots, to allow the part to expand when the screw was tightened.
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_9598Medium.jpg)
Of course, I had to dress the shoulder up to true it, so I'd have been better off not machining the shoulder until this point, but no matter.
The result is this fairly brutal fixture. I had to turn the OD of the screw slightly so that it would fit through the collar hole. No big deal.
With that done, I could mount the wobble plate.
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_9599Medium.jpg)
The fixture worked a treat. Admittedly, this is somewhat making mountain out of a molehill, but I saved the part, and learned some stuff. It's all good. I turned the plate to the right thickness, and all was well with the world.
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_9600Medium.jpg)
It is a pretty ugly, tarshled screw. I usually throw those out - I'm surprised it was in my odds and ends screw jar, but it did the job.
Next I made the collar. It is a simple part - so not too many pictures here. Basically, the trick is to machine it close to the diameter of the ID of the wobble plate, and then take small finish cuts off the OD, test fitting the plate, until you can get the plate to sit firmly at the correct angle. I suppose I could have done the trigonometry to calculate the required diameter, or even laid it out on CAD (which I know would have met with disapproval), but in the end taking light cuts until the correct fit is achieved works perfectly well.
After that, I parted the collar to length, and added a threaded hole (4-40 rather than the 3-48 on the plans - because I have 4-40 grub screws in stock).
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_9603Medium.jpg)
You can see the little remnants of blue that I used to help mark the hole position - that will clean off when I prep the parts for soldering.
Next up - the cylinder.
The plans show a plain brass cylinder, soldered to the cylinder head, of 0.5" OD and .375" ID.
I saw someone somewhere add some fins, just for aesthetics, and I thought that was a splendid idea, so I followed suit. I increased the OD to 0.625", and then cut some grooves, about 0.1" wide, leaving fins of 0.05". The fins should come flush against the side plate, I should not need to increase the length of the valve or the crankshaft to match it - although that is another valid option.
First cuts:
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_9605Medium.jpg)
A little further...........
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_9607Medium.jpg)
Most of the fins done
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_9608Medium.jpg)
After the fins were all machines, and the edges lightly chamfered to remove burrs, I drilled and reamed the bore to 3/8. Then I cleaned up the end, and parted off the cylinder.
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_9612Medium.jpg)
The cylinder just needs deburring at the parted end, and then a light face to length, and it is complete, and ready for soldering to the cylinder head once that is made.
Here are the parts so far:
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_9613Medium.jpg)
Plenty to do yet, but I am 5 for 5 so far - no scrap on this project yet! :whoohoo:
Tomorrow - perhaps the cylinder head and piston. I'll see how I feel.
-
If the scoring was not too bad, you could have cleaned up the back of that disc by rubbing it on a piece of wet and dry :ThumbsUp:.
Jo
-
You are making some good progress there Prop. Still following along with enthusiasm here!!
Bill
-
Sorry to be a late comer. Missed the start of this while I was sick.
I think I've only seen one other engine like this. It'll be a an interesting read.
I look forward to it.
-
Prop, you are moving right on along. I gonna have a lotta catch'n up to do. Your surface finish does appear to be spot on. Keep up the good work and I'll be watching. Great pics too.
Eric
-
If the scoring was not too bad, you could have cleaned up the back of that disc by rubbing it on a piece of wet and dry :ThumbsUp:.
Jo
An excellent point. At the time, I really badly wanted a nice, smooth and machined finish both sides.
Of course, having achieved that, it dawns on me that I am going to solder this disc onto the collar later, and after that it will need some sort of clean up anyway, so in this case it would have been quicker and easier to just clean up on the wet and dry as you suggest. :facepalm2:
It just goes to show how you have to think about making the part all the way through to the conclusion, including its integration with other parts, not just the next one or two steps. No big deal though, making the little collet wasn't a bad exercise and didn't waste a lot of time.
I'm quite enjoying this project, I should be able to get out in the shed for a bit today. Maybe tackle the cylinder head, piston and valve.
-
You are making good progress Prop. I like what you did to the cylinder. Keep the photos coming, and I do like brass by the way. It's cuts easier and molds easier then steel. A little more expensive but perfect for first projects.
Don
-
Thanks all. All comments, suggestions, hints and tips greatly appreciated.
I spent a little more time on this today, and I shall now show you my triumphs, and point out the screw up. Although I yet hope to recover from the screw up. You'll see what I mean.
So, I started the day off by doing a last little bit of finishing to the cylinder - nothing to much to note there. It simply needed facing to length at each end, and then a chamfer on the ID of the bore at one end, for extra clearance for the con rod.
With that done, I decided to make the piston. Starting with more brass.
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_9614Medium.jpg)
I measured the ID of the cylinder bore, and then ever so gradually snuck up on it on the OD of the piston, test fitting the cylinder over it as I went.
Here you can see my sneaking. ;D
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_9615Medium.jpg)
Once the OD was achieved, I needed to make two counterbores, one 1/4" diameter, and another 5/16, to allow for clearance for the con rod. I drilled out most of the material, but finished both counterbores with end mills.
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_9616Medium.jpg)
That worked out quite well.
With that done, I added the two oil grooves. I just used a threading bit to make the light cuts.
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_9620Medium.jpg)
After parting off, I turned the piston around and cleaned up the end.
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_9621Medium.jpg)
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_9623Medium.jpg)
I am very happy with how it fits in the bore of the cylinder. It slides very nicely.
-
Now, I was going to work on the cylinder head today, but in the end decided to have a go at the con rod.
I started by cutting a piece of 1/4" dia brass rod about 3" long, and put a center drill to it at one end. Then I mounted it in the 3 jaw, and supported the other end with a dead center.
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_9627Medium.jpg)
I put a smidge of high temperature grease used for disc brakes on the dead center. Not sure it was necessary, but figured it couldn't hurt either.
Now, I started with a light clean up skim over the whole length to clean up and get the OD concentric, and then focussed on the small diameter.
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_9629Medium.jpg)
Gradually taking cuts to get close to the desired diameter, and then taking several very light finish cuts to smooth it out.
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_9630Medium.jpg)
After that, I machined the little end down to the right diameter (little end is at the tailstock end)
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_9631Medium.jpg)
And now is when I screwed up. I very carefully turned down the diameter past the little end to separate the piece of unwanted support material from the con rod.
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_9632Medium.jpg)
It went fine - but the screw up is - I have no way to hold the part to mill the flats and drill the hole through the little end! Gah! :rant:
I think I can recover from this with this technique - what you can see here is a simple two piece clamp that I made, which allowed me to hold the con rod and clean up the little end.
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_9633Medium.jpg)
It does work:
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_9634Medium.jpg)
I think I will be able to use such a technique to support the part for adding flats and pivot holes. What I should have done was leave the excess material each end - milled the flats and drilled the holes, and then parted / turned off the excess. You live and learn, but like I say, I think I can recover.
The parts cache as it stands:
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_9636Medium.jpg)
Tomorrow - well tomorrow is bloody marys and brunch with my friends, so there won't be any machining tomorrow, but the next session will likely involve the cylinder head I think. I'm going to put off finishing the con rod a bit so that I can mull over the flats and holes and give them my best shot when I'm ready.
:embarassed:
:ROFL:
-
A couple of suggestions...
Putting the oil grooves in a piston can raise tiny, almost invisible burrs that increase the effective diameter ever so slightly. I take the piston down to ten or fifteen thousandths oversize, make the grooves, and then finish cut to size. Any burrs formed are removed by the final cut.
Making the connecting rod in one piece might be good as an exercise but whenever I encounter such a piece I try to dissect it into separate components and make a fabrication. That's what I did on my version of this engine.
As you learned, make the flats first. Drill the hole(s) before disturbing the setup so the holes are perpendicular to the flats. Then do the turnings.
Have you given any thought to how you are going to fixture the swash plate to solder it to the sleeve to which it attaches? That gave me the most trouble when I made the engine.
-
A couple of suggestions...
Putting the oil grooves in a piston can raise tiny, almost invisible burrs that increase the effective diameter ever so slightly. I take the piston down to ten or fifteen thousandths oversize, make the grooves, and then finish cut to size. Any burrs formed are removed by the final cut.
Sure enough, when I went to test fit the piston after completion, it no longer fit in the cylinder because of those burrs. Not a big problem to remove, but I should have done it in the order you mentioned here. Now I know for next time, anyway.
Making the connecting rod in one piece might be good as an exercise but whenever I encounter such a piece I try to dissect it into separate components and make a fabrication. That's what I did on my version of this engine.
As you learned, make the flats first. Drill the hole(s) before disturbing the setup so the holes are perpendicular to the flats. Then do the turnings.
I definitely need to start thinking through the sequence of events more carefully. When I made the flywheel on the last engine, I actually listed out the machining sequence on the white board. I may try that again on more complex components in the future, in writing it down it helps highlight when things may not be sequenced best. However - today I have thought of a scheme that will allow me to mill the flats and drill the holes, and save the part. I will try it tomorrow I hope. However, in future the sequence will be different.
EDIT: This is one reason why this hobby is so much fun. It exercises the brain - it's not just about turning metal.
Have you given any thought to how you are going to fixture the swash plate to solder it to the sleeve to which it attaches? That gave me the most trouble when I made the engine.
I have given it some thought, although I wouldnt say I have arrived at a final decision. basically it involves a spacer under one side of the disc, and a weight on top of the hub to hold it down. But I don't want the weight to be a heatsink and make the soldering difficult. So, still working through that idea.
EDIT: What might work, is if I use a clamp - think of a longish arm to apply some pressure to the top (one end) of the hub. Then a spacer under the "high" end of the plate should hold it in the right position - I was careful in turning the hub down so that when the disc is wedged at a tight angle, it is in the right position. I have a few odds and ends of ceramic about, which could go on top of the hub so that whatever arm I use to apply pressure doesn't act as a heat sink. In my minds eye, this arrangement is perfect and flawless, so naturally that makes me suspicious of it. ;)
-
Toldya! :mischief: About the burrs I mean.
Yes, machining is far more a mental discipline than it is a physical skill. It's one of the few hobbies where an advanced case of OCD is a real aid to performance. You'll learn a great deal about how your mind works (or not) from this hobby.
Think everything about the part through first. Material selection, single piece or fabrication, how to hold, how to install, etcan. - it's all important, especially so if you're designing on the fly like so many of us do when making jigs, fixtures, tools, and accessories.
You'll soon learn to do this in your mind while performing routine daily chores. (My favorite is showering but doing dishes or scraping paint works well too.) Novices should probably start by doing it on paper so they can appreciate in retrospect just how much there is to think about. For complex jobs everyone, novice or accomplished, should use paper.
I didn't silver solder the swash plate on my engine. It will never get hot enough, even running on steam, to melt the silver-bearing conventional solder I used. The engine has seen many running hours and it shows no weakening.
I made a little aluminum (won't stick to solder) jig to hold the plate and the piece to which it attaches. A small setscrew provided the necessary tilt. Then I tilted the jig so the swash plate was horizontal (to minimize solder runoff), applied flux and some flux-coated paillons of solder to the joint and blazed away with the torch.
-
Of course had you told me about the burrs before I made the part instead of afterwards.........;)
No matter Though - not a difficult problem to rectify, but it is more satisfying to get the job done and not have to rectify things. This engine though is proceding with less rectification than the first one, so I take some satisfaction from that.
For the wobble plate assembly I was just going to use tin/lead solder. I think it will do the job well enough. On a job like this I usually wind a piece of solder around the joint before heating, coated with flux, and then heat the joint indirectly with a torch. ie heat top and bottom of collar, and the disc, moving between each until the solder flows, and then that is it. Usually works a treat - it sounds a lot like the method you outlined. I find it best to set the job up entirely this way, rather than heat and try and poke a stick of solder at it, for example, which usually ends up with knocking the parts over and solder running everywhere. I'll take pictures when I do it of course, and we'll see how it all works out.
-
:Lol: This thread brings back many memories when I was starting out a few years ago.
You're absolutely right about this hobby exercising the brain. Problem solving. That's a big part of the joy.
-
... and pain.
-
Yes. Pain. Well - emotional pain anyway. ;D
We try and keep body and soul together of course!
-
OK - so I thought I would share my attempts at saving the con rod. It sort of worked out. Sort of. I am undecided as to whether to make the whole thing again or not. As you will see, it certainly needs some clean up, which is no big deal I guess.
What is clear from all this is that I could really use either a mill, or I need to add a vertical slide to the lathe somehow. Short term that may be what I do.
Anyway, here is what I did.
I started by mounting the con rod in the toolpost, in a V cut tool holder, using the split collar I made. I used the other tool holder position to hold a piece of aluminum bar to support the big end of the con rod, and then milled the first flat.
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_9639Medium_zps35489ec0.jpg)
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_9640Medium_zpsf146e8db.jpg)
Then I applied some blue to that face, and marked the position of the crank pin hole.
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_9642Medium_zps664f1b09.jpg)
I then drilled that hole.
Then, I rotated the con rod, and used the drill hole to align the rod to the axis of the lathe, to prepare it for milling the second side.
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_9644Medium_zps60dc6313.jpg)
After milling:
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_9645Medium_zpsd4966e0b.jpg)
Then I flipped the part around to work on the little end.
Again, I used the drilled hole in the big end to get the orientation of the part.
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_9646Medium_zpscad1c422.jpg)
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_9647Medium_zpse66f95be.jpg)
Once the first flat was milled on the little end, I again used the big end hole as a locator, and then used the cross slide to index across the appropriate distance for the hole in the little end, center drilled it, and then through drilled it. Again, I rotated the part around and milled the second side.
It worked out, more or less.
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_9648Medium_zps1ac7ccdc.jpg)
As you can see, the finish is awful, so I will have to clean up with emery and so on, but I will accept that for now. In future I will machine such parts in a more appropriate sequence.
Getting this done was tricky, without a nice fine adjustment to the vertical position, but sometimes you have to make do with what you have - and this did at least get the holes drilled accurately in terms of their spacing relative to each other.
Next up, Cylinder head, which requires the 4 jaw. I made a simple center test indicator bar to help align it.
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_9650Medium_zps8b7acb0b.jpg)
It's a solid rod - no spring as yet, I will make a nicer one in due course.
I also made progress with the CNC router, and have managed to create programs for it and drive it, so sometime this week I hope to try cutting the side plates for the engine. I still have a few things to work out on that.
-
That looks good Prop, given the way you had to go about it. A little clean-up on the flat faces with some fine emery paper an dyou should be good to go. Keep after it.
Bill
-
Thanks Bill.
Of course, the little CNC router might be a good tool for this as well, but it has a really limited tool set. If I can spot hole positions though, that might help. Don't know - I'll look into it.
-
Nice save Prop.
Did I hear a 'whew!'?
-
Nice save Prop.
Did I hear a 'whew!'?
You did - and a few other interesting expressions too. :naughty:
-
Good going Prop :ThumbsUp:
Ahh... Files and emery - they get to be one's best friends ;)
Kind regards, Arnold
-
Well done Prop, like Arnold said files and emery are you pals when it comes to clean ups.
Don
-
Thanks Fellas. I am trying to work towards the goal of not having to attack every component with emery paper in order to make them look acceptable, but Rome wasn't built in a day, after all. I think you need to balance the long term perfection goals with near term success to give a boost along the way.
Anyhoo, I was out in the shed today, and made some progress on the cylinder head.
This is a rectangular part, with a circular boss on it that locates the cylinder for soldering later. I suppose you could machine the whole thing from solid, although the 1/16th hole from cylinder to valve would be tricky.
Anyway, here it is in the 4 jaw, all blued up, ready for alignment.
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_9651Medium_zpsb18bb06c.jpg)
I used the procedure that Marv kindly wrote up in my "request for center finder" thread. I had made a simple center finder, as a solid bar with taper on one end and center hole on the other, and this all worked a treat. I had the center hole located very quickly with Marvs method. I was very happy about that.
Once it was centered, I scribed a 3/8 circle in the blue on the face of the part, as a visual aid. I then started facing the part down to the right thickness, leaving a bit over the 3/8 circle (wish I had taken a picture).
Once the part was at close to the right thickness (leaving some to skim off the opposite side), I then turned the boss to the correct OD, and then faced it to length.
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_9652Medium_zps08da1971.jpg)
After that, it was a case of marking out and drilling the various holes in the part to completion .
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_9654Medium_zps0b4bdd32.jpg)
Again, there are aspects about this part that I am dissatisfied with. I won't go into details. but improvement will be necessary. Right now, I want to use the component as is and see how well it works.
I also worked on the valve, which is a very simple part - a rod with a reduced diameter part way along its length.
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_9655Medium_zps02f43826.jpg)
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_9656Medium_zpse0e858f4.jpg)
I am now rapidly approaching a point where I HAVE to make some progress on the base and side plates, and they will be the focus of the upcoming weeks work, I think.
-
You are making some fine progress Prop. By next weekend i predict you will be ready for a trial run.
Bill
-
You are making some fine progress Prop. By next weekend i predict you will be ready for a trial run.
Bill
+ 1 You're doing very well! Nice looking parts.
-
I just ran across this build log, as I just started to build my copy of Elmers #14 Wobble Plate engine! Since I am a bit short of brass for the cylinder, I decided to use a 30-06 shell cartridge. There was enough length to it, about the right I.D., and I drilled and polished the bore and it is looking good!
I just completed Elmers #5 Geared engine, and it was and is a great project.
So Prop, how are you coming on this the Wobble Plate engine? Regards, Karl, CM
-
You will like the #14 too Karl. I always thought it was one of Elmer's more interesting valve motions even if not patterned after a prototype engine (at least not that I know of).
Bill
-
I loved building the wobble plate. It's a nice runner when you get it timed. Enjoying watching the build
Dave
-
I second that. A fun build for me. One of my Elmer's favorites.
Don't know if Prop just stopped posting the log or ???
If you have any questions, there have been more than a few built here. Just ask.
Here's a video of the first run on mine.
https://www.youtube.com/watch?v=R_Ozg6j57X4
-
Nice video of your Elmers #14 Stan. Here this season in Michigan, with all of the extreme cold, and being retired, gave me time to snuggle up to my Sherline and Unimat SL lathes and build and complete my Elmers #5 Geared engine! Now as I am getting into my build on the Wobble Plate engine, the weather is getting warmer so I will have to hurry before all of my outdoor activities start up. I to, wondered about Prop's build log, and not seeing any further progress; we can just hope that he is okay. Regards, Karl, ChipMaker
-
I too hope he's OK.
If you're going to NAMES, I'll have mine there. Sometimes it helps to see it live.
-
I am planning on going to NAMES this year; I have missed a couple of the shows for various reasons. I have gone to many of them, even entered the Sherline contests with an entry, especially when my grandson was young and we "baby sat" for him. He would build and engine of some sorts and have an entry. It was fun. Hope to see you there. Karl ChipMaker
-
I agree this is a fun engine to make and a bit different to the other wobblers, I thought I would add a few of my pictures and my solution for holding the wobble disc while soldering. https://www.youtube.com/watch?v=9NwwORo7TE4
Geoff
-
That looks like a very effective soldering jig - it obviously worked! Hugh.
-
Ahem.
So, last post on the matter was February 2013, so, here we are in December 2015, I suppose I should get on with it. :embarassed:
I stepped out to go to the shops and................................ :facepalm2:
Anyway, a lot happened in the last nearly 3 years, just not on my engine. :censored: But never mind all that. Thanks to everyone for your interest and concern, I really appreciate it, actually.
I still want to finish this engine, and progress HAS been made, albeit it not much.
I have done some work on the frame and plates.
This is a test fit. I don't have pictures of the parts as I was making them. Although the finish on these is not very good, I am happy that the holes line up. I located all holes by using an edge finder and then the machine dials, rather than by marking out and center punch. I DID mark out the plates, as a visual aid. The two bearing holes were made by clamping the two plates together to get the datum edges flush, so as to keep the bearings aligned for the shaft.
Pay no attention to the use of countersunk screws - this is just a test fit to make sure things line up properly.
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3504%20Large_zpskblpenb7.jpg) (http://s291.photobucket.com/user/propforward/media/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3504%20Large_zpskblpenb7.jpg.html)
Yesterday, I made the valve arm guide. Here it is marked out.
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3508%20Large_zps4wudb6o6.jpg) (http://s291.photobucket.com/user/propforward/media/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3508%20Large_zps4wudb6o6.jpg.html)
Again, the marking out is more as a visual aid. I used a slitting saw to make the 1/16" cut in the guide. That went quite well, but overall I am not happy with how the part turned out (hence no pic of the "finished" part). I think it would "work", but the more I thought about it during the night (staying awake thinking about it - a sure sign that it isn't right) the more I want to do over on that part.
Better progress was made on the crank disc. I saw arnoldb make a crank disc this way, so I tried the technique. The first two times I royally screwed up the part through simple novice errors, or perhaps simply not paying enough attention. After the second time I became quite disheartened, and that's one reason the engine got shelved for a while.
However, I got it right yesterday, by carefully making a big diagram on my shop white board, with coordinates, and notes about which way to turn the cross slide handles to get the slides to go in each direction. Yep, got that wrong once, and ruined an otherwise perfect part. *sigh*. Sometimes I wonder whether I should even be doing this hobby, but I figure it's all about practice.
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3519%20Large_zps3vncfjyz.jpg) (http://s291.photobucket.com/user/propforward/media/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3519%20Large_zps3vncfjyz.jpg.html)
I think I will be able to make the center hole on the lathe, part off the crank disc and then face it size once it is mounted on the crankshaft. :ThumbsUp: I already drilled the hole for the crank screw for the connecting rod.
This little bit of success has given me a boost, although the poor quality of my lever guide took the wind out of my sails a bit. However, only one thing to do - grit ones teeth, figure out what I didn't do right and go at it again.
I've still got a lot going on, so it may be two weeks before I get back to the shop, but I am determined to finish this engine this winter.
In other news, I got to go to a threshing show of immense proportions here in Minnesota this last September, with more engines in one place than I have ever seen before - it's amazing. So I'll try and post pictures about that in the general area of the forum.
-
Good to see you back working on the #14 Prop! Keep after it and you will have a nice runner there. Still one of my favorites of Elmers engines.
Bill
-
Thanks Bill, as always it was great fun to make chips again.
It's very pleasing to see a couple of other people have posted their wobble plate engines above - some really nice work there, more inspiration. Very interesting soldering jig by Geoff - simple and effective, and I really like his boiler and engine set up.
sshires engine is a lovely runner, I hope mine runs like that. I must finish it so that I can find out. ;D
I did test fit the piston in the bore yesterday, and that feels pretty good, so I have high hopes.
More in due course!
-
Good to see you back, Prop. Good to see the progress. Cheers, Hugh.
-
A bit of progress. My good buddy Oskar:
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3530%20Large_zpskrk9y7mr.jpg) (http://s291.photobucket.com/user/propforward/media/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3530%20Large_zpskrk9y7mr.jpg.html)
and I went over to the shop yesterday, and continued work on this little beastie.
First off, I re made the lever guide. The one I made two weeks ago probably would have "worked", but it wasn't very good. The slot wasn't properly centered, and holes weren't quite aligned....and various things. Anyway, it simply didn't represent what I can really do, so I made it again, and I have to say I feel really good about that.
I used my lathe to turn the little block to the correct length. Last time I used my mill, and I didn't get it square. This time I got it nice and square.
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3535%20Large_zpsitk9bfus.jpg) (http://s291.photobucket.com/user/propforward/media/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3535%20Large_zpsitk9bfus.jpg.html)
I used a slitting saw to make the slot:
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3536%20Large_zpsovaizlyv.jpg) (http://s291.photobucket.com/user/propforward/media/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3536%20Large_zpsovaizlyv.jpg.html)
I am getting in the habit of using edge finders and machine dials to locate holes and features, but I still blue the parts and mark them out sometimes, as a visual aid.
It's not exactly an impressive part, but nevertheless an important part of the engine.
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3539%20Large_zpsztzidifc.jpg) (http://s291.photobucket.com/user/propforward/media/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3539%20Large_zpsztzidifc.jpg.html)
Turns out I broke the tapping drill I need to finish this part two weeks ago, so I can't finish it just yet. Still, with all holes either drilled or spot faced, I moved on.
I drilled the center hole on the crank disc (I also did some clean up on a couple of edges of the crank, which were not great, and I'm happy with how that turned out).
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3531%20Large_zpsb1af3vhr.jpg) (http://s291.photobucket.com/user/propforward/media/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3531%20Large_zpsb1af3vhr.jpg.html)
I have now run into a bit of difficulty. I broke the drill off in the top hole (not the center hole). :Doh:
I am pretty sure I can save it though. I have started parting off the crank disc, and have stopped at the top hole (the broken drill is too hard to cut through). I'm going to carefully grind through the broken drill bit, then finish parting off the disc. I am pretty sure I will be able to get the drill bit out then, as I will have access to it from both sides. Also, I have plenty of material on the crank disc, so that I can finish it to thickness afterwards and will be able to remove any grinding damage. Nasty, but that's where we're at. More on that after Christmas when I get back to it.
Other work performed - I started making the crank screw:
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_2418%20Large_zpspnzwrxjh.jpg) (http://s291.photobucket.com/user/propforward/media/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_2418%20Large_zpspnzwrxjh.jpg.html)
Turns out I don't have the threading die I need, so that part is also on hold now until I get the die.
I also made the crank shaft, but didn't take a picture. Once I get the crank disc parted off, I will press it onto the shaft, and finish machining the disc to thickness.
Here is my collection of parts for the engine - slowly taking shape.
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_2419%20Large_zpsm7ftgyja.jpg) (http://s291.photobucket.com/user/propforward/media/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_2419%20Large_zpsm7ftgyja.jpg.html)
I bought a cast flywheel for it, mainly for fun, and also to have a "first pass" at machining a casting. After this engine I intend to take a leap and take on a casting kit.
-
Nice collection of parts so far. That flywheel is pretty big for this engine though it should work ok. Still following along.
Bill
-
That wheel is a bit of a big lump. Bit like me, really.
-
Prop
Looks like you're getting near the end. It will run. Mine started up first time (amazement).
-
Thanks Bill and Stan, I appreciate your encouragement. Next time I go to the shop I hope to make up a soldering jog and solder the wobble plate and also the cylinder and head assembly. Then I'll be pretty close. Hoping to finish this by new years, but won't be too put off if I don't. (I've let it sit this long, after all :D)
-
Well, I had intended to go to my shop and do some machining today. However, we are under threat of a foot of snow, and since I now have to drive an hour to get to my shop, decided to do other things and wait until the storm passes.
That said, the storm has yet to actually arrive, so I could have gone anyway.
Be that as it may, I did take a moment or two to take a dremel to the crank, and grind through the troublesome drill bit that I broke off. Happily, everything went well and I ground through the bit, and was also able to poke the remnants out of the crank disc.
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3558_zpsubkfwqno.jpg) (http://s291.photobucket.com/user/propforward/media/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3558_zpsubkfwqno.jpg.html)
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3559_zps5ydtgjxn.jpg) (http://s291.photobucket.com/user/propforward/media/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3559_zps5ydtgjxn.jpg.html)
It's ugly, but there is more than enough material to be able to clean the disc up to the correct thickness once parted off, so I think I've managed to save this.
The chatter marks are a bit ugly though. Must improve on that.
Next opportunity to do more will be this coming thursday, friday and saturday. Hopefully 3 solid days of fun in the shop - a new years treat!
Happy New Year everyone.
-
Quick update. I managed to get a couple of hours in the shop yesterday. I had hoped to get more time over the holidays but that didn't happen. But yesterday was fun and productive.
I finished up the crank disc. Parted it off and pressed it onto the shaft, and then machined it to thickness and finished it. I also finished off the crank screw and did a test assembly.
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3578%20Large_zpsab9ymzem.jpg) (http://s291.photobucket.com/user/propforward/media/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3578%20Large_zpsab9ymzem.jpg.html)
It was actually very much a day of finishing up partially made components. There were several parts that were awaiting holes and slots, so I wrapped those up.
The lever guide - here shown being test fitted to the rest of the frame:
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3580%20Large_zpsoza4z9cg.jpg) (http://s291.photobucket.com/user/propforward/media/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3580%20Large_zpsoza4z9cg.jpg.html)
That all looks a bit rough at the moment, but I think once I've cleaned it up it will look reasonable. There are some chuck marks on the head that I'm not happy about, but I have to solder it all up yet, so we'll see how it looks after that.
Valve - which needed slot and hole for link pin:
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3582%20Large_zpszry7rket.jpg) (http://s291.photobucket.com/user/propforward/media/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3582%20Large_zpszry7rket.jpg.html)
And I also added the pin hole to the piston:
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3584%20Large_zpsvwr32yhb.jpg) (http://s291.photobucket.com/user/propforward/media/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3584%20Large_zpsvwr32yhb.jpg.html)
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3585%20Large_zpscurfsqvy.jpg) (http://s291.photobucket.com/user/propforward/media/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3585%20Large_zpscurfsqvy.jpg.html)
The reason these aspects had been waiting, is because I had to do some more basic test machining using the edge finder. I did my practice runs on the frame, using the edge finder to locate a zero reference, and then use dials to position the cutting tool / drill correctly. Anyway, that all seemed to go well, so I'm a step further along now.
Next, I'll polish up the frame assembly, press in the bearings and test the crank shaft fit. Then I'll make a solder jig for the wobble plate, and solder that, and also the cylinder to the head. Then all I have left is the lever pisvot, lever and flywheel. So - coming along!
-
The crank disk came out swell.
You mention pressing it onto the shaft. I can't tell from the picture...is the shaft pressed into a thru hole or a blind hole?
The piston looks good too. How did you cut the grooves?
-
Thanks!
It's a through hole in the crank disc. I made the shaft end slightly longer than the thickness of the disc, so that I could skim them back together. I made myself sharpen the cutting tool, and mixed a fresh batch of coolant before starting yesterday, so I got a finish I am happy with on both.
The grooves in the piston were made with a thread cutting tool (for the V point) and just cut using the lathe. But I made a mistake, because I cut them AFTER finish machining the diameter of the piston, so that threw up a burr. It was easily polished off, but in future I'll get the piston near size, machine the grooves, then finish the diameter.
-
Everything looks great. Should be running before you know it.
About the Chuck marks. Make some copper or brass jaw covers. Thin copper sheet like heavy roof flashing is easily formed around each jaw and elimates the jaw marking.
-
Thanks Stan! I shall do that - one of those tips that really can make a massive difference to the finished article. :ThumbsUp:
-
More nice progress! Not too many bits left now until this one will be a runner. Still one of my favorites of Elmer's engines and you are doing it proud!!
Bill
-
Chuck marks. Make some copper or brass jaw covers. Thin copper sheet like heavy roof flashing is easily formed around each jaw and elimates the jaw marking.
Once you've made a sort of U-shaped piece to fit on the jaw, cut two slits into the verticals of the 'U' so you can bend the resulting tabs so-formed around the first step in the chuck jaw. This will keep them in place while inserting/removing the workpiece.
-
Thanks Fellas, I really appreciate the input. I'll do exactly that on the jaw guards.
There's as much work making jigs, fixtures, tools and accessories in this hobby as there is in making the actual engines. Yesterday I had to make some simple small V blocks for holding small diameter components. It is all part of the fun and interest.
-
A few more hours in the shop today - and a bit more progress. It was a case of one step forward, one step back, then two steps forward. A bit frustrating, but that's the way it goes.
I made the lever arm pivot today, but it took me two attempts. I won't show pictures of how badly the first one turned out, but it was a real mess. After wasting time on that, I took a breather, and instead of machining installed my coolant reservoir and pump on my lathe. Didn't take long, but I had to make a hole and install a hose fitting in the chip tray. That gave me just the breather I needed to gather my thoughts and try again.
First time I made the pivot, I used aluminum. The second time, I used brass. Only because I had decided that having the brass pivot would add a little more contrast to the engine when finished.
This is pretty obvious, but it's an easy step to short cut, and do yourself a disservice, especially as a novice like me. I have made too many scrap parts lately, so now I have started by sketching the part I am making up on my whiteboard, and writing the steps I intend to take. This helps me think through the part before I start.
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3612%20Large_zpsnkjtzduj.jpg) (http://s291.photobucket.com/user/propforward/media/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3612%20Large_zpsnkjtzduj.jpg.html)
So I took my piece of brass, and first of all got it nicely squared up in the lathe, then transferred it to the mill, where I used an edge finder to locate the part.
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3608%20Large_zpsfqt4mdk2.jpg) (http://s291.photobucket.com/user/propforward/media/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3608%20Large_zpsfqt4mdk2.jpg.html)
Then I milled the sides away to form the "upside down T" shape
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3609%20Large_zps87tojzuh.jpg) (http://s291.photobucket.com/user/propforward/media/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3609%20Large_zps87tojzuh.jpg.html)
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3610%20Large_zps2y1hlmp6.jpg) (http://s291.photobucket.com/user/propforward/media/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3610%20Large_zps2y1hlmp6.jpg.html)
Then I mounted a center drill and spot faced the part for the two mounting holes.
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3611%20Large_zpsmaz5hudp.jpg) (http://s291.photobucket.com/user/propforward/media/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3611%20Large_zpsmaz5hudp.jpg.html)
Then drilled the holes out
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3613%20Large_zps6todpbni.jpg) (http://s291.photobucket.com/user/propforward/media/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3613%20Large_zps6todpbni.jpg.html)
After that I turned the part round in the milling vise, and spot faced the three pivot hole positions
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3614%20Large_zpsd2rcfnfi.jpg) (http://s291.photobucket.com/user/propforward/media/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3614%20Large_zpsd2rcfnfi.jpg.html)
Then drilled those out.
Then I set up the slitting saw, and made the slit for the lever arm.
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3616%20Large_zpsvx3unabx.jpg) (http://s291.photobucket.com/user/propforward/media/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3616%20Large_zpsvx3unabx.jpg.html)
After that I removed the part from the vise, and transferred to the lathe. I chose to machine this component from an over length piece of bar stock, just to have plenty of material to hold. So after making the holes and doing the bulk of the machining, I used the lathe to part the component off, leaving extra material, and then finished the part to size in the milling machine.
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3617%20Large_zps4rlotonf.jpg) (http://s291.photobucket.com/user/propforward/media/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3617%20Large_zps4rlotonf.jpg.html)
This worked out quite well.
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3618%20Large_zpsbnyechvo.jpg) (http://s291.photobucket.com/user/propforward/media/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3618%20Large_zpsbnyechvo.jpg.html)
It is not perfect - but it is reasonable. As usual, it is set up and checking everything is square and true that I need to focus on. Getting the basics right makes for a better part. So I am more and more forcing myself to slow down at the start, not just jump in, and this is leading to better parts, with better finishes.
I should get back to the shed next weekend, and keep this going.
-
Well that second one turned out just fine Prop. You shouldn't have too many more bits to make at this point! I think you are really going to enjoy watching this one run!!
Bill
-
Thanks Bill, it's great to have you following along.
All I have left now is the lever arm, and 3 pins (valve pin, lever pivot pin, piston pin), flywheel and input tube for the steam (or more likely compressed air). I also have to solder the cylinder head and wobble plate assemblies. Then it's a case of polish it up, assemble and test.
In order to solder the wobble plate I need a jig. I had hoped to make that today, but having two goes at the lever pivot block put paid to that. :insane:
-
As to planning before cutting, that's exactly what I do. If there are more than a few operations, I do write them down. This generally prevents me from "painting myself into a corner." It's usually something like removing something that I need to hold the part for the next step. I'll even do the part in my head to see if I can pick up any problems. I too had to learn to slow down. Keep at it.
-
Well, moving right along now - I managed to get a few more hours in the shop. It was supposed to be two days - in which case i would have had this finished - but things conspired to prevent that.
Anyway - I set up my wobble plate and hub with a 1/8" spacer to hold the plate, and soldered the plate into position.
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3621%20Large_zps31icrmdd.jpg) (http://s291.photobucket.com/user/propforward/media/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3621%20Large_zps31icrmdd.jpg.html)
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3623%20Large_zpsnyonnidu.jpg) (http://s291.photobucket.com/user/propforward/media/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3623%20Large_zpsnyonnidu.jpg.html)
Looks messy, but cleaned up just fine.
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3627%20Large_zps7rxxbwqa.jpg) (http://s291.photobucket.com/user/propforward/media/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3627%20Large_zps7rxxbwqa.jpg.html)
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3628%20Large_zpswwl1jn5a.jpg) (http://s291.photobucket.com/user/propforward/media/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3628%20Large_zpswwl1jn5a.jpg.html)
Although the errant blob of solder is a bit annoying. I should be able to polish that off though.
I also set up the cylinder and head assembly
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3625%20Large_zps0pjxsrtj.jpg) (http://s291.photobucket.com/user/propforward/media/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3625%20Large_zps0pjxsrtj.jpg.html)
And soldered that
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3626%20Large_zpstcov9wgu.jpg) (http://s291.photobucket.com/user/propforward/media/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3626%20Large_zpstcov9wgu.jpg.html)
It still needs a bit more cleanup, but is looking OK. I don't have a pic of the cleaned up assembly at the moment.
I started making the pivot pin for the lever arm
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3633%20Large_zps2lqhpi7d.jpg) (http://s291.photobucket.com/user/propforward/media/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3633%20Large_zps2lqhpi7d.jpg.html)
And also started on the lever arm itself.
Marking up:
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3634%20Large_zpsyauqnptx.jpg) (http://s291.photobucket.com/user/propforward/media/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3634%20Large_zpsyauqnptx.jpg.html)
And spot drilling the holes
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3635%20Large_zpsc1uvcxwy.jpg) (http://s291.photobucket.com/user/propforward/media/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3635%20Large_zpsc1uvcxwy.jpg.html)
As well as that, I started work on the flywheel. I faced one side, and then set the wheel up for a 45° tapped hole for a set screw to lock it to a shaft.
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3629%20Large_zpskkwx3sls.jpg) (http://s291.photobucket.com/user/propforward/media/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3629%20Large_zpskkwx3sls.jpg.html)
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3631%20Large_zpsv6k61fay.jpg) (http://s291.photobucket.com/user/propforward/media/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3631%20Large_zpsv6k61fay.jpg.html)
That's as far as I got today. So close now.........
-
Great update prop. Yes you are so close now. I predict a runner very soon!!
Bill
-
I think that wobble plate looks great.
It always amazes me how things clean up.
But you make me feel ashamed too. My clamping kit looks pretty messy. I guess it's time to do some deep cleaning. ;D
-
Prop
It's really coming together. The bits completed so far look great. Looks like a winner.
Zee
What is it you do with your clamps that require deep cleaning? :ROFL:
-
I soooooooooooooo wish I could have had all weekend in the shoppe, I'd have this finished. Not to worry - nearly there. I have brought most of the parts away with me to start clean up for assembly, so once the lever arm and flywheel are finished I can put it together and test it. :ThumbsUp:
And, er, the reason my clamp set is so clean is that it hasn't had nearly enough use. Must get more shop time in. :embarassed:
-
So let me ask this - or rather let me describe my sequence for machining the flywheel, and then ask - does that sound right? Or do you use a different method?
1. Hold flywheel on the cast OD in the lathe chuck.
2. Face off front edge of hub and outer wheel.
3. Center drill and drill / bore hub
4. Drill and tap set screw thread into hub.
5. Mount flywheel on a shaft.
6. Use the shaft to hold the flywheel in the lathe chuck.
7. Machine OD of flywheel to size
8. Face off / clean up hub and wheel faces.
Is this how you go about it? I can't see another way of holding the flywheel so that you can get a nice, clean, uniform finish across the OD. On some flywheels where the hub is a large size and gives you some good material to hold that is possible of course.
Any other tricks?
-
Prop, the problem with holding the flywheel on a shaft is that it isn't rigid enough and you are likely to get some chattering when cutting the OD of the flywheel. Your first three steps are fine but I would suggest turning the underside of the rim while everything is still square in the lathe so it will be concentric with the hub/bore. This then gives you an ID surface to chuck on once you turn the flywheel around. If the bore is still concentric with the lathe axis using the three jaw chuck then fine. If not you may have to use the 4 jaw and an indicator to get the bore centered with the lathe axis. Then you can turn the OD of the flywheel with a more rigid setup. I would also suggest tailstock support since you may not have a lot of surface are to chuck on (depth) but even so this will be much more rigid IMHO than mounting the flywheel on a rather small shaft.
Bill
-
Ah yes, OK, makes complete sense. Thanks Bill, I'll do that.
This wheel has a fair bit of material to get jaws in to hold the inside of the rim - I see now that that will work very well.
Looks like I'll get to practice with my 4 jaw and center finder again! :Lol: :ThumbsUp:
EDIT: I also just found a nice article by Marv from his website, with some good advice.
I intend to move on to a casting kit after this engine is finished - and the reason for adding this (somewhat oversized) casting to this bar stock engine, is simply as a first look at castings and the additional work / different techniques required to work with them.
-
I'm with Bill...machining a wheel held on a shaft can lead to chatter.
If you're comfortable with holding it by the inside of the rim then go with that. In cases where you might not feel good about doing that an alternate approach is to clamp the partially machined wheel to a chunk of stuff using straps over the spokes and leaving the rim exposed. Clamp the chunk in the 4jaw and get the wheel bore running true, then machine the rim.
What article of mine did you find? The one about centering stuff in the 4jaw?
-
What article of mine did you find? The one about centering stuff in the 4jaw?
This one
http://www.schsm.org/html/machining_small_castings.html
In it you describe the approach that you mentioned above.
I like both approaches. When I am back in the shop I'll see which seems most appropriate.
-
This one
http://www.schsm.org/html/machining_small_castings.html
In it you describe the approach that you mentioned above.
I like both approaches. When I am back in the shop I'll see which seems most appropriate.
My gosh, I'd completely forgotten that I'd written that. Losing one's memory is one of the most insidious and depressing things about aging. Perhaps the second most depressing thing :-)
BTW, that isn't my website. It belongs to the local HSM club to which I used to belong. Of course, in a sense, the "Articles" sub-section is mine since virtually all the articles were written by me.
-
Landmark day today.
I spent the day working on the last two parts - lever arm and flywheel. The flywheel is not actually finished - you'll see why in a bit.
The lever arm was straightforward, not much to report there. Once I had it finished, I did some clean up on the parts amassed so far, and began assembly. Pretty much everything went OK. The crankshaft fits through both bearings and turns, and the lever arm was mounted on the central hole. I wasn't sure that I had enough travel at first, but my test run was successful (video later).
I actually did a test run with the mostly unmachined flywheel, just to see how things were - and since I had a positive result I put some more effort into the flywheel before shooting some video.
This is what I contrived to hold the flywheel. The picture shows the wheel being set up with centerfinder.
(http://i291.photobucket.com/albums/ll286/propforward/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3664%20Large_zpsv5hutmcb.jpg) (http://s291.photobucket.com/user/propforward/media/Steam%20Engines/Elmer%2014%20Wobble%20Plate/IMG_3664%20Large_zpsv5hutmcb.jpg.html)
It's very simple - just a machined disc with two holes for screws to fit through. The disc fits closely into a machined bore on the rim of the flywheel. I tried machining the rim first, but found I could not hold the rim on my chucks, so I made this jig instead. It worked well, except that although I got the bore of the hub centered well, I did not properly align its axis, so the flywheel doesn't run true. I shall rectify that, but for now, here is some preliminary footage. Oh - I didn't have a set screw for the flywheel - so excuse the ugly countersunk screw. But I really wanted to see it run. ;D
Overview - just a look around the engine while it runs. Running at about 20 and then increased to 30 psi.
[youtube1]https://youtu.be/F33EdQugnOs[/youtube1]
Slow speed run - about 12 PSI, and as slow as I could get it to go without stalling
[youtube1]https://youtu.be/l_1UjRclyOI[/youtube1]
So - summary.
I am happy with how the engine runs - it runs at low air pressure and low speed, so I think overall fit of parts is good. Also, the lever arm runs in its center position - so for the most part I think I am satisfied with what I have made.
There are imperfections though. Most of these don't show in the pictures but some do.
Damage to parts through work holding.
True / squareness of parts
Finish of cuts - especially on the mill
These are the primary areas I think I need to address. I need to spend some more time setting up my mill especially, and getting everything true and square.
I was dead set on moving on to a casting kit after this engine. I'm not convinced I did well enough to really be sure I can do a fair effort to a casting kit - but then again sometimes you just have to try. I'll think about it.
I want to make some jigs and tools, so if after some set up work those come out well, then I may try my hand at castings. That's really the direction I want to go.
-
Wonderful result prop!! You have every reason to be elated with how it looks and runs. Castings do present different challenges, but you are up to it so don't shy away from a simple to moderate casting set. Well done on the wobble plate engine.
Bill
-
Prop:
Very nice little engine, and it runs very well. Congratulations.
I haven't tackled a casting set either. It's not a major goal for me but I'll likely try it sooner or later. Casting sets seem expensive, but I haven't added up all the orders for a bar stock engine either. In a bulk purchase I obtained a casting set for a Tiny Power model two cylinder steam engine. I don't think I'm up to that but it's on the shelf when I do. I'll be interested in your casting build. What models are you considering?
Thanks for the build thread, and again congratulations.
Hugh
-
That little guy runs very nicely. So many won't run that slow!! Great work.
Pete
-
Nicely done and looks great.
Congrats!
Do you have a particular casting in mind?
-
Thanks folks, I really appreciate and enjoy your positive comments. I learned a lot on this engine (another way of saying I screwed up some stuff ;D), but not everything had to be made twice. In fact most parts were correct first time, so to speak.
I have a PMR number 1 casting set on hand. I chose it because as casting sets go it seemed a decent price, looked challenging without being too overwhelming, and also is a fairly large size. I actually had some difficulty holding small parts on the Elmer engine - but of course there are tricks and techniques to that too.
-
The PMR #1 is a nice engine Prop. I think there are a couple of build logs here on MEM, including the one I did about a year ago. They may give you some ideas if and when you tackle the castings. One good thing about the PMR kits is that they can provide replacement castings if needed...good people to work with.
Bill
-
Bravo! :cartwheel:
Beautiful runner. I agree that one test is slow speed running. Just about anything will run if you throw enough air pressure at it. Slow speed I.e. Low pressure shows how well you built this engine.
Regarding castings. The PMR #1 is a good choice as there are build logs that are very helpful.
I avoided castings for quite a while (I think I had built 8 or 10 engines before I summonded up the nerve.)
Also, I wanted to build a larger engine as I was trying to avoid the tiny "fiddle bits."
The first was the Rider-Ericsson ¼ scale. After reading Bill Lindsey's build log about 200 times, I went for it. Different challenges to ge sure; mainly in work-holding.
As Bill said, the PMR guys are great and will give advice and will replace individual castings (as did Clarence Myers on the Rider.)
Go for it!
-
Thanks again!
I'm actually relieved to hear that you both agree with me on my choice of the PMR 1 - gives me more confidence to try. And really - that's the thing, it's good to just try. Some stepping stones along the way make sense, to keep the number of learning experiences inside sensible limits. ;D
I didn't know of the Myers engines - I just looked them up - very nice indeed!
I have been looking at the build logs - especially Bills - for the PMR 1, and it is really great to have that background to research before making a start. I am looking forward to kicking off, but first some careful machine tool adjustment and set up, and some jigs and fixtures. I'm also seriously considering obtaining a much smaller 4 jaw chuck for my lathe. Maybe a 3 jaw as well.
-
Well done indeed! This is one of my favorite engines and you've done a great job on it.
I wish I could have had the assistance of this forum when I first ventured into castings. Between build log background and one or two day answers to your questions from the resident experts, you shouldn't have any problems at all.
I found that the most important advice with castings was to force yourself to have the patience to completely think through the entire machining process on each part and write a procedure sheet to follow. It's admittedly painstaking but skip it and you'll quickly learn why I think it's so essential. Once you get some casting experience under your belt you can relax a bit on this but at first...
-
Thanks Marv, that is high praise indeed.
You are so right on your methodical approach. I found this on the barstock parts too. It is simply best to write down the plan first. Then follow it through again, and revise a few times before making the first cuts. It seems time consuming at first, but saves time in the long run.
This is a really fun engine, I enjoyed making it and I'm happy with the result, overall.
-
Looking forward to seeing the PMR #1. I like its looks.
I don't think it's for me yet though. 6 1/2 flywheel seems big for my mini.
-
Congratulations Prop! Very nice runner you built there.
This is a very interesting little engine. I like it!
Kim
-
I brought it to work today for show and tell. ;D :ROFL:
-
And did everyone oooooh and aaaaah over it as they should have?? Its definitely worthy of that :)
Bill
-
Haha! You're too kind.
Well,they did ooh and ah to an extent (as polite enthusiasm requires), but it was mentioned that they (my co workers) like my cake baking and home brewing experiments better.
Bah! Heathens. Although my good buddy suggested I should actually use it to drive one of those silhouette figures of a woodsman with an axe, which I have to admit would be a lot of fun.
-
Well,they did ooh and ah to an extent (as polite enthusiasm requires), but it was mentioned that they (my co workers) like my cake baking and home brewing experiments better.
Bah! Heathens.
Heathens indeed. They apparently don't know how to keep the cake and brews coming.
They should suffer.
-
And they will, make no mistake. There will be no friday donuts this week, then we'll see whether the enthusiasm level increases. :stir:
-
Looking great on the Youtube videos!
I haven't made an engine yet (working on a boiler first) but if it's anything like as good as this when I do I'll be well pleased :)
-
Thanks! Plenty of areas for improvement, but I'm pleased at how this ran. I'll be putting some time into adjusting lathe and mill to get them adjusted better, then onto a set of castings.