Model Engine Maker

Engines => Your Own Design => Topic started by: yogi on November 11, 2016, 06:20:31 AM

Title: Freelance Inline Twin
Post by: yogi on November 11, 2016, 06:20:31 AM
Hello everyone,

The days are getting shorter and the temperatures cooler, which draws one back into the shop. So itís time to introduce you to my next project. After the hit Ďn miss engine I built last, I want to build a multi cylinder engine. Iíll keep it relatively simple, as it will be a two cylinder engine.

The engine is totally freelance and designed by myself. The main part of my design is the built up crankshaft. The inspiration for the crankshaft comes from H. Shillings. It utilizes large thin section ball bearings to register the different parts accurately. The idea is to have easy to make parts that will be assembled to a true running crankshaft.

The goal will be to have a slow idling, well running engine. I set the compression ratio at 5.5 : 1. This figure is just a stab in the dark, as I havenít built an engine like that before. The slow idle is important to me, and I feel I can achieve what Iím looking for with the mass of the flywheel and crankshaft combined.

The engine is built up from bar stock. Throughout the design, I tried to simplify the parts as much as possible without compromising the look too much.

It will be liquid cooled, requiring a full set up with pump, fan and radiator and all. Thatís another first for me.

A few dimensions to get a feel for the size; Bore 32mm, Stroke 34mm, Flywheel diameter 90mm, Height to top of cylinder head 178mm

Below, I have some CAD renderings for you guys. This is how the finished engine should look like. There are still a few little details that need attention, but I feel confident enough in the design to have a go at it.

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20001%201024x770.jpg)

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20002%201024x951.jpg)

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20003%201024x878.jpg)

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20004%201024x828.jpg)


I hope you will be along for the ride..

Yogi


Title: Re: Freelance Inline Twin
Post by: Roger B on November 11, 2016, 07:10:55 AM
Looks an interesting project  :ThumbsUp:  :ThumbsUp: Is that the waterpump behind the fan? I'm not sure that you will really need the number of crankshaft bearings that you have unless you will be running the engine with high loads/speeds  :headscratch:
Title: Re: Freelance Inline Twin
Post by: Jasonb on November 11, 2016, 07:16:32 AM
Looks Intertesting, Malcom Stride had a couple of basic designs using the Schillings type crank but never got round to making them, not unlike your engine in many ways.

Roger the bearings form part of the crankwebs and without them the built up crankshaft would not work, Schillings used the method in a number of engines upto V8 or maybe even a V10. Though I think it should only need the centre bearing and two small outer ones.

J
Title: Re: Freelance Inline Twin
Post by: yogi on November 11, 2016, 07:43:01 AM
Roger, yes, that is the pump behind the fan.
Like Jason said, the bearing are an important part of the built up crankshaft, and not only for the load bearing. Especially for our small engines.
The outer bearings could be smaller, but when I started to draw up this project, it was a four cylinder, which I then reduced to two. I left it modular like that to test the design.
It is an experiment, even though I have confidence it will work well. I guess the only way to find out is to build one...  8)

Yogi

Title: Re: Freelance Inline Twin
Post by: Zephyrin on November 11, 2016, 09:10:26 AM
Very nice project, i enjoy to follow this thread...
I didn't see any output from the camshaft to drive the distributor, are you planning to use glow plugs ?

I have an inline four (still unfinished) with this sort of crankshaft and when all the pieces are apart on the bench, it looks very tricky to assemble in the engine bloc...but really clever at the end!!
Title: Re: Freelance Inline Twin
Post by: gbritnell on November 11, 2016, 01:30:58 PM
Yogi,
On thing you might think of in the initial design stages is to make accommodation for a one-way bearing in the flywheel for starting purposes. Since I adopted this type of setup on my engines for starting it sure makes it much simpler.
Another thing I noticed it doesn't look like you have much room between the camshaft and the pushrod to allow for lifters.
gbritnell
Title: Re: Freelance Inline Twin
Post by: toolznthings on November 11, 2016, 03:09:31 PM
Hi Yogi,

Like the crank design. Will follow along closely, even though it's in metric.  :ROFL:

Your friend,
Brian
Title: Re: Freelance Inline Twin
Post by: yogi on November 11, 2016, 04:18:25 PM
Zephyrin, I'm planing on an electronic ignition, with a lost spark. Both plugs firing at the same time, so no need for a distributor. I like the crankshaft you built there. That is exactly along the lines of what I'm trying to do here.

George, thanks for your input. Not sure what you mean with a one way bearing, like a overrunning clutch? If so, yes, I have thought about it. The crankshaft will have a thread at the end of it (it's not modeled in the rendering, just showing the major diameter). The reason for that is I'm not sure what the engine is going to drive if anything. I'm hoping it would be a candidate to drive a generator. A little genset. The thread leaves me with options on how to adapt it to different things, including a starting dog.
Please see the cross section of the cam/lifter arrangement. The guides are threaded into the block, and could easily be made longer if need be. Any feedback is greatly appreciated.

Thanks Brian, you know I like to work in metric, as there are fewer decimal points!!!  :stickpoke:


(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20005.jpg)



Title: Re: Freelance Inline Twin
Post by: Dave Otto on November 11, 2016, 04:41:08 PM
Nice looking engine Yogi.
It will be fun watching it come into reality.


Dave
Title: Re: Freelance Inline Twin
Post by: 10KPete on November 11, 2016, 07:06:21 PM
This promises to be very interesting, Yogi. I like the layout so far. I do question having both crank throws in line as I've never seen an engine like that. Usually the two throws are 180* apart. Will it balance the way you have it drawn??

Keep it coming!   :popcorn:

Pete
Title: Re: Freelance Inline Twin
Post by: Admiral_dk on November 11, 2016, 07:48:56 PM
A 360 degree crank is the way almost all old English twin motorcycle engines where made  :old:

A modern version would be with either a 315 degree or a 270 degree crank as the give a much smoother running with a balancer shaft.

I like your design Yogi and would certainly be along for the ride  :cheers:
Title: Re: Freelance Inline Twin
Post by: yogi on November 11, 2016, 10:03:56 PM
Thanks guys, good to have you on board.

Pete, I debated hard over a 360 vs a 180 degree crank. I ended up deciding on a 360 degree crank even though the imbalance is a concern. The big advantage of this design is if it doesn't work, it will be a matter of undoing two screws and I can change it to a 180 degree crankshaft.

Title: Re: Freelance Inline Twin
Post by: 10KPete on November 11, 2016, 10:54:29 PM
The big advantage of this design is if it doesn't work, it will be a matter of undoing two screws and I can change it to a 180 degree crankshaft.

True! Duh, hadn't thought of that....

Pete
Title: Re: Freelance Inline Twin
Post by: gbritnell on November 11, 2016, 11:02:05 PM
Except you'll have to make a new cam when you do that. Just saying.
gbritnell
Title: Re: Freelance Inline Twin
Post by: yogi on November 12, 2016, 02:00:29 AM
That's right George. Except I'll stay with the spirit of this engine and the camshaft will be built up as well. So it would be a matter of "timing" the two cam lobe sets accordingly.


(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20006%20800x413.jpg)

Title: Re: Freelance Inline Twin
Post by: 10KPete on November 12, 2016, 02:33:44 AM
Yep, Yogi has it all figured out.....   :facepalm:

Pete, just waiting to see this one run!
Title: Re: Freelance Inline Twin
Post by: yogi on November 12, 2016, 03:59:28 AM
I hope I thought of everything Pete, but please feel free to ask questions, or if you have any input I sure would like to hear it. Right now would be the time to make a change to the design.

The design evolved over a long time. I have been working on it on and off for over two years. So there were a lot of design decision that had to be made. It's also my first IC engine I designed myself and I'm curious to see if everything is going to work out the way I imagined while drawing it up.

Regards,
Yogi
Title: Re: Freelance Inline Twin
Post by: Jasonb on November 12, 2016, 07:00:39 AM
360degree crank should be OK The Nemett Bobcat which is a similar layout model engine runs OK with one, the designer did an article or two about crank layout Vs vibration and decided the 360 was the best for his engine.
Title: Re: Freelance Inline Twin
Post by: gbritnell on November 12, 2016, 01:01:59 PM
Hi Yogi,
I'm guessing that the cover plate on the head is so you can create water passages in the head and then seal it off? If this is correct then you might have some issues with the valve guide alignment as they go from the head to the cover plate. I might suggest putting a couple of registration dowels in the head and cover plate so that the two pieces stay in exact alignment when machining and assembling.
gbritnell
Title: Re: Freelance Inline Twin
Post by: yogi on November 12, 2016, 03:45:37 PM
Thanks Jason, that is comforting to know.

George, thank you for your input. You are correct. The top plate is so I can seal off a cooling passage machined into the head. I came up with the following solution to the problem you pointed with the valve guides alignment: The holes for the valve guides in the cover plate will be machined over size, to allow for the machining tolerance. Also, the valve guides will be stepped down to a smaller diameter at the top. This would prevent the valve guide from working its way out of the cylinder head from the combustion pressure. Even though to common practice of pressing them into the head has proven to be more than adequate, I felt this would be worth while.


(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20007%20800x472.jpg)


Best Regards,
Yogi

Title: Re: Freelance Inline Twin
Post by: Roger B on November 12, 2016, 06:14:58 PM
Do you need the port tapered in towards the outside like that? Parallel and matching the manifold would be much easier to machine  ::)
Title: Re: Freelance Inline Twin
Post by: yogi on November 12, 2016, 08:48:09 PM
Roger, the exhaust passage is actually a straight hole, but it's at an angle to clear all the mounting holes. The section cut was done parallel to the plane, that's why it looks tapered. To better illustrate, I attached a couple of renderings.

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20009%20800x462.jpg)

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20008%20800x553.jpg)


Regards,
Yogi

Title: Re: Freelance Inline Twin
Post by: kuhncw on November 12, 2016, 10:15:39 PM
Yogi,

I like your twin cylinder design.  It reminds me of the Bob Shores Silver Bullet I built.  I think you'll find you can easily start your engine with a hand crank.  Definitely add the over running bearing as George mentioned. 

Which solid modeling software are you using?

Good luck and I'll be following your build.

Chuck
Title: Re: Freelance Inline Twin
Post by: yogi on November 13, 2016, 12:17:33 AM
Thanks Chuck!

I modeled the engine in Solidworks.

Regards,
Yogi

Title: Re: Freelance Inline Twin
Post by: b.lindsey on November 13, 2016, 12:31:49 AM
Very interesting project Yogi. I have been following along quietly and will be along for the ride.

Bill
Title: Re: Freelance Inline Twin
Post by: Art K on November 13, 2016, 03:13:12 AM
Yogi,
Just caught your inline twin. It looks like the makings of a great engine. Your cad work is way above mine, I must admit. I look forward to seeing it progress.
Art
Title: Re: Freelance Inline Twin
Post by: yogi on November 13, 2016, 02:21:00 PM
Thanks Bill and Art!
I hope it's going to work the way I envisioned it...  ;)

Title: Re: Freelance Inline Twin
Post by: kuhncw on November 14, 2016, 03:57:08 AM
Yogi,

What is in the big ends of your rods for bearings?

Since you are going for low rpm idle, don't hesitate to add some extra diameter to the flywheel.  If that makes the flywheel look a bit large, you could add an industrial engine style flywheel housing.

Chuck
Title: Re: Freelance Inline Twin
Post by: steamer on November 14, 2016, 12:22:29 PM
Looks very "Wallabyish"   8-)

I like the crank! 

Dave
Title: Re: Freelance Inline Twin
Post by: yogi on November 14, 2016, 09:20:22 PM
Chuck, the big end bearings will be needle roller bearings. A bigger flywheel is always an option. I think we'll have to wait and see how it runs, and make adjustments if needed.

Dave, I definitely used some design ques from Westbury's Wallaby. It is such a good looking engine...   8)

Regards,
Yogi

Title: Re: Freelance Inline Twin
Post by: yogi on November 16, 2016, 04:56:04 AM
It's time to make some chips!  8)

I wanted to start with the crankshaft, but since the bearings I ordered haven't arrived yet, I decided to have a go at the crankcase.

To illustrate what it should look like when finished, I'll start this post with a couple renderings of the crankcase halves. Correct me if I'm wrong, but I think this will help some people to visualize the different set ups.

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20010.jpg)

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20011.jpg)

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20012.jpg)


First, I squared the block on 3 faces. Looking at the picture below, the faces in the jaws are already finished to size. This will be the with of the crankcase, and the bottom is machined, that will be the reference for the thickness. I must admit, I didn't take a pictures while I did the squaring, as it is nothing special and I didn't think people would be interested, but it would help describe the process...   :facepalm:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20013%20800x450.jpg)


I started with the inside of the two halves. The pockets which will make room for the con rod to work in are next.
Bellow a couple of "action shots" while machining. It was quite a time consuming op, as the pockets are rather deep with a small cutter. A small step over and conservative feed rate are a must...

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20015%20800x450.jpg)

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20016%20800x450.jpg)


The pockets are machined out...

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20014%20800x450.jpg)


...and cleaned up.

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20017%20800x450.jpg)


Stay tuned,
Yogi

Title: Re: Freelance Inline Twin
Post by: yogi on November 17, 2016, 03:53:45 AM
The work continued on the outside of the crankcase halves:

First, milled the "flange" where the two halves will be screwed together. Second operation was the angled relief. To note here is the part is sticking out of the vice rather far. This is definitely not ideal, but doable with some caution.

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20018%20800x450.jpg)

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20019%20800x450.jpg)


The bottom half at this stage:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20020%20800x450.jpg)


The same process was used for the top half of the case, except one side is different where it will house the camshaft.

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20021%20800x450.jpg)


The two halves put together for the first impression of where this engine is going...  8)

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20022%20800x450.jpg)


Stay tuned,
Yogi
Title: Re: Freelance Inline Twin
Post by: tvoght on November 17, 2016, 02:55:32 PM
Yogi, I've been watching with interest. I think the 3D renderings do help to visualize the setups. Nice work so far.

--Tim
Title: Re: Freelance Inline Twin
Post by: yogi on November 20, 2016, 03:52:17 AM
Thank you Tim!

The next step is to bore out the case for the crank and camshafts.

The two halves are screwed together and set up in the vise.

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20023%20800x450.jpg)


Bore for the camshaft first:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20024%20800x450.jpg)


...and for the crankshaft:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20025%20800x450.jpg)


At this stage the case was faced over to ensure the surface is perpendicular to the bore, and the hole pattern for the cover was drilled. The operation was repeated on the other side, machining the case to it's final length and drilled the hole pattern.

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20026%20800x450.jpg)


The last operation was to drill and bore the top to finish the case.

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20027%20800x450.jpg)


The finished crankcase (minus a few threads needing to be tapped  ;) )

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20028%20800x450.jpg)

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20029%20800x450.jpg)


Stay tuned,
Yogi

Title: Re: Freelance Inline Twin
Post by: b.lindsey on November 20, 2016, 04:07:15 AM
Wow yogi, you are moving right along. Very nice looking crankcase so far too. Staying tuned for more!!

Bill
Title: Re: Freelance Inline Twin
Post by: yogi on November 21, 2016, 08:20:07 AM
Thanks Bill! It's going to slow down, as life keeps interfering with my shop time...  8)
Title: Re: Freelance Inline Twin
Post by: Perry on November 21, 2016, 10:31:30 AM
Hello Yogi, nice engine there. quite simmilar to my freelace endeavour,
btw after carefull balancing there was no problem with vibrations at all.

search topic "2 cylinder OHV 29ccm"

regards
Peter
Title: Re: Freelance Inline Twin
Post by: Nick_G on November 21, 2016, 01:01:15 PM
.
Impressive.  :)

Nick
Title: Re: Freelance Inline Twin
Post by: yogi on November 24, 2016, 09:10:42 AM
Thanks guys!  :cheers:

Peter, yes, the engine you built has a lot of similarities to what I'm trying to accomplish. Hopefully it will turn out as nice as yours.

Here the link to Peters engine build thread for easy reference:
http://www.modelenginemaker.com/index.php/topic,4173.msg77420.html#msg77420


Regards,
Yogi


Title: Re: Freelance Inline Twin
Post by: yogi on December 13, 2016, 01:35:06 AM

The work continues on the crankshaft.

First, some lathe work.
Here, the rear (flywheel end) of the crankshaft beeing turned:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20030%20800x450.jpg)

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20031%20800x450.jpg)

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20032%20800x450.jpg)

The crank discs were turned next:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20034%20800x450.jpg)

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20035%20800x450.jpg)

What will be the front end of the engine (the accessory end):

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20036%20800x450.jpg)

After all the parts were finished turned, it was over to the mill. I machined a set of soft jaws, to be able to hold the part accurately on the bearing seat. It is very important that the hole for the crank pin is not only accurate in diameter, but also exactly perpendicular, for everything to line up when assembling the crankshaft.

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20037%20800x450.jpg)

Two of the discs where drilled to be tapped, and two countersunk.

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20038%20800x450.jpg)

The front and rear part being finished as well:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20039%20800x450.jpg)

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20040%20800x450.jpg)

The different parts, ready for assembly:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20041%20800x450.jpg)

...and the assembled crankshaft:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20042%20800x450.jpg)

The crankshaft installed in the crankcase:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20043%20800x450.jpg)

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20044%20800x450.jpg)

To demonstrate how free its running, a short video:

OyHVQv1lLTo
I'm very pleased how the crankshaft and the project has turned out so far, and hope the rest of the engine will go as smooth...

Stay tuned,
Yogi
Title: Re: Freelance Inline Twin
Post by: steamer on December 13, 2016, 02:06:32 AM
Oh I am definitely gonna do an engine with a crank like that.....That's slick!


Nice Job!

Dave
Title: Re: Freelance Inline Twin
Post by: Roger B on December 13, 2016, 09:35:45 AM
Very nice  :praise2:  :praise2: Your hand gives a good idea of the size of this engine.
Title: Re: Freelance Inline Twin
Post by: Orloff on December 13, 2016, 05:19:39 PM
Well done, I'm speechless. That is impressive.
Title: Re: Freelance Inline Twin
Post by: Admiral_dk on December 13, 2016, 07:47:20 PM
Looking really good Yogi  :praise2:

Can you tell me what size bearings you used here ?

Best wishes

Per
Title: Re: Freelance Inline Twin
Post by: fumopuc on December 13, 2016, 07:54:34 PM
Hi Yogi, very nice and precise job. First time I have the possibilty to see someone making this crank concept of Mr. Schillings. His book is now since 4 or 5 years on my desk.
Title: Re: Freelance Inline Twin
Post by: yogi on December 13, 2016, 10:43:42 PM
Thanks everyone for the kind comments. Much appreciated!  :cheers:

Per, the bearings are 61810  50x65x7 mm


Regards,
Yogi

Title: Re: Freelance Inline Twin
Post by: Dave Otto on December 13, 2016, 11:29:29 PM
Very nice work on everything so far Yogi!
Were the crank pins pressed in place?

Dave
Title: Re: Freelance Inline Twin
Post by: b.lindsey on December 14, 2016, 02:29:49 AM
Not to repeat but simply beautiful work Yogi!!  Still following along intently here.

Bill
Title: Re: Freelance Inline Twin
Post by: Art K on December 14, 2016, 04:21:38 AM
Yogi,
This is looking very impressive. If I understand the crank construction correctly Dave the outer part of the web encloses the pin and locks it in place. The only way out is removing the bolts that hold the two halves of the web together. Yogi will there be any lubrication system?
Art
Title: Re: Freelance Inline Twin
Post by: yogi on December 14, 2016, 07:09:28 AM
Thanks for the comments guys!  :cheers:

Dave, the original idea was to use Loctite for the pins, but the fit turned out so well (a very light push fit) that I think it doesn't need it.

Art, you are correct, the pin can't go anywhere, as it is locked axial in place. I did have some concerns about the bending forces that might work on the crank pin, hence the Loctite for additional insurance. Now that I hold the crank in my hands, and can feel how solid it is, my gut feeling is that I will be working just fine the way it is.
It will be splash lubricated.

Yogi
Title: Re: Freelance Inline Twin
Post by: Zephyrin on December 14, 2016, 08:14:03 AM
Great work with this crankshaft, impressive and inspiring for model engine builders !
Title: Re: Freelance Inline Twin
Post by: yogi on January 06, 2017, 03:41:58 AM
Thank you Zephyrin for the kind comment!

The next part Iíll be making is what I call the cylinder block. The challenge on this part will be the O-Ring groove and the cavity for the liquid cooling. The first picture is a sectioned rendering to illustrate how the finished part should look.

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20045%20800x563.jpg)

I started with squaring the block on 5 sides on the Bridgeport.

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20046%20800x450.jpg)

I then moved the work over to the CNC mill where the top side was faced over and two holes for the bores were pre-drilled. To rough out the two bores I used a long end mill and a helical interpolation. This is by no means the most efficient way when it comes to metal removal rate but it works very well with the long end mill. Another benefit is that it will produce the right size bore so itís not going to take many passes with the boring head to get it to size.

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20047%20800x450.jpg)

And bored out to finish size using a boring head.

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20048%20800x450.jpg)

For the O-Ring groove I used a small slitting saw. The saw is 1 x 0.043Ē
The groove is quite deep down in the bore making it a bit nerve wracking as itís impossible to see the cut. Itís one of those ďletís hope the code is rightĒ momentsÖ

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20049%20800x450.jpg)

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20050%20800x450.jpg)

To relief the block for the coolant I used a T-slot cutter.

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20051%20800x450.jpg)

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20052%20800x450.jpg)

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20053%20800x450.jpg)

The next operation was to mill a step to seat the sleeve.

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20054%20800x450.jpg)

The last operation on the top of the block was to drill the holes for the cylinder head and coolant passages.

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20055%20800x450.jpg)

To top side finished:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20056%20800x450.jpg)

The block is then turned over to drill the mounting holes at the bottom.

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20057%20800x450.jpg)

The bottom ďflangeĒ is milled.

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20058%20800x450.jpg)

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20059%20800x450.jpg)

And the passage for the coolant inlet is drilled.

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20060%20800x450.jpg)

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20061%20800x450.jpg)

Last, the step on the sides were milled. This is a cosmetic feature as I needed a bit more length on the cylinder head but didn't want to lengthen the crankcase.

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20062%20800x450.jpg)

The finished cylinder block.

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20063%20800x450.jpg)

The engine is taking shape:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20064%20800x450.jpg)


Stay tuned,
Yogi


Title: Re: Freelance Inline Twin
Post by: Roger B on January 06, 2017, 08:09:37 AM
Excellent  :praise2:  :praise2: I need to look further into using a slot cutter for maching out the water spaces although I will have to use Steve Huck's manual version  ::)
Title: Re: Freelance Inline Twin
Post by: stevehuckss396 on January 06, 2017, 05:17:34 PM
Really nice looking engine.  Great job man!
Title: Re: Freelance Inline Twin
Post by: Dave Otto on January 07, 2017, 01:40:35 AM
The cylinder block looks great Yogi.
The family shot also looks very nice!




Dave
Title: Re: Freelance Inline Twin
Post by: cfellows on January 07, 2017, 06:47:01 PM
Really nice machine work!  The design looks great, too!

Chuck
Title: Re: Freelance Inline Twin
Post by: b.lindsey on January 07, 2017, 04:55:58 PM
Fine looking engine Yogi.  Looking forward to your continued progress !

Bill
Title: Re: Freelance Inline Twin
Post by: yogi on February 04, 2017, 04:46:29 AM
Thanks everyone for the kind comments. Itís much appreciated!

The next part for the engine will be the covers to finish the crankcase. Iíll let the pictures do the talking rather than me trying to explain the steps, so please feel free to ask any questions if I leave anything out.

The front cover (accessory end) is milled on the CNC mill.
First, face milling the top:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20065%20800x450.jpg)

Spotting and drilling the hole pattern:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20066%20800x450.jpg)

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20067%20800x450.jpg)

Roughing the contour:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20068%20800x450.jpg)

Milling the counter bores:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20069%20800x450.jpg)

Finishing pass:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20070%20800x450.jpg)

And an edge break around the contour with the spot drill:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20071%20800x450.jpg)

First side finished:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20072%20800x450.jpg)

I decided to make the gear cover as well, as I can use the same tools and similar set ups.
Again, first step was a face cut:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20073%20800x450.jpg)

Spotting and drilling:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20074%20800x450.jpg)

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20075%20800x450.jpg)

Roughing:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20076%20800x450.jpg)

Milling the relief for the screw heads:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20077%20800x450.jpg)

Finishing pass:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20078%20800x450.jpg)

Edge break:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20079%20800x450.jpg)

First side of the gear cover done:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20080%20800x450.jpg)

A set of machinable soft jaws were installed in the vise and milled out for the second side operation.
 
(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20081%20800x450.jpg)

Second side of the cover finished, still in the vise:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20082%20800x450.jpg)

Another pocket in the soft jaws was milled out to finish the second side of the gear cover.

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20086%20800x450.jpg)

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20087%20800x450.jpg)

The finished parts:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20083%20800x450.jpg)

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20084%20800x450.jpg)

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20088%20800x450.jpg)

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20089%20800x450.jpg)

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20090%20800x450.jpg)

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20085%20800x450.jpg)


Stay tunedÖ



Title: Re: Freelance Inline Twin
Post by: stevehuckss396 on February 04, 2017, 12:21:29 PM
Very nice!  The gear case looks a little bare. Maybe you could engrave something on it like a logo of some kind or the name of the engine when you figure it out.
Title: Re: Freelance Inline Twin
Post by: zeeprogrammer on February 04, 2017, 01:47:24 PM
Awesome project yogi and the parts look fantastic!

It may have been asked before...tell me about your cooling system on the mill.
Title: Re: Freelance Inline Twin
Post by: yogi on February 05, 2017, 04:38:51 AM
Thanks guys! :cheers:
Good idea for an engraving Steve. I will revisit the idea later when it's time for assembly...

Zee, I'm using my own version of a FogBuster coolant sprayer.

Yogi

Title: Re: Freelance Inline Twin
Post by: yogi on February 19, 2017, 08:19:39 PM
To continue the work on the crankcase, The cover for the flywheel end is next.

This was a straight forward turning job, so it will be a relative short post.

First, I turned the inside:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20091%20800x450.jpg)

The part was flipped over, to finished the outside:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20092%20800x450.jpg)

..and the last operation on the mill to drill the hole pattern:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20093%20800x450.jpg)

The finished part:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20094%20800x450.jpg)

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20095%20800x450.jpg)


Stay tuned

Title: Re: Freelance Inline Twin
Post by: 90LX_Notch on February 19, 2017, 08:34:40 PM
Geez, I don't know how the heck I missed this thread until today.  What an awsome project.  You have my respect Yogi.  This is really a neat build.

-Bob
Title: Re: Freelance Inline Twin
Post by: b.lindsey on February 19, 2017, 09:23:07 PM
Fine looking parts yogi!! It's going to be a fine looking engine too!!

Bill
Title: Re: Freelance Inline Twin
Post by: yogi on March 02, 2017, 04:13:52 AM
Thanks for the kind comments Bob and Bill. Always appreciated!  :cheers:

The next part for the engine are the connecting rods. The big end will have a needle roller bearing, and the small end a bronze bushing.

As for you guys that have been following this build already know, I'll be using the trusty soft jaws for this part again.

The first side is machined to the full depth plus a little extra. The stock is chosen to allow sufficient material to hold it in the vise.

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20096%20800x450.jpg)

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20097%20800x450.jpg)

A set of soft jaws was milled out, to hold the rods for the second side machining:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20098%20800x450.jpg)

The extra stock is milled off and the rods machined to final thickness.

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20099%20800x450.jpg)

The finished connecting rods:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20100%20800x450.jpg)

Thanks for following along, and stay tuned for more...
Yogi


Title: Re: Freelance Inline Twin
Post by: mnay on March 06, 2017, 07:24:15 PM
Yogi,
I used that same method for similar parts.  It works great.  I did not think to mill some  soft jaws to hold it like that.  I learn something new everyday from the forum.  Thanks for posting.
Nice looking rods

Mike
Title: Re: Freelance Inline Twin
Post by: Dave Otto on March 07, 2017, 12:33:46 AM
The rods look great Yogi!


Dave
Title: Re: Freelance Inline Twin
Post by: Art K on March 07, 2017, 02:45:18 AM
Yogi,
I have to agree with everyone else, the rods look great. Did you bore the ID's to fit the bearings or do a circular interpolation?
Art
Title: Re: Freelance Inline Twin
Post by: yogi on March 07, 2017, 04:59:19 PM
Thank you guys for the kind comments!  :cheers:

Art, I used a circular interpolation to machine the ID's. The bearing has a slip fit and will be secured in the rod with adhesive.


Yogi


Title: Re: Freelance Inline Twin
Post by: toolznthings on March 07, 2017, 05:14:20 PM
Looked even better in person !! Love it !  :cartwheel:

Brian
Title: Re: Freelance Inline Twin
Post by: yogi on March 25, 2017, 06:53:00 AM
Thanks for the kind comment Brian! Much appreciated!  :cheers:

Progress on the engine has slowed down to crawl lately, as work has been interfering with precious shop time...  :rant:  :insane:  ;)

The cylinder sleeves are made, and ready to share with you guys.

The sleeves are turned from cast iron bar stock.
The first side is turned to size on the inside and outside:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20101%20800x450.jpg)

After parting off, the sleeves are finished on the second side. The small shoulder will create a groove in the cylinder block for an O-ring.

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20102%20800x450.jpg)

Finish turned:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20103%20800x450.jpg)

...and that's how they look installed in the cylinder block:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20104%20800x450.jpg)

The finish in the bore turned out very nice, and was cylindrical within less then 0.01 mm. I contemplated to just leave it as is, just turned. But I decided to finish lap the bore. Since the surface finish was already really good, and the bore straight, the lapping took mere minutes to complete. (note the cling film on the lathe bed, to protect it from any lapping compound).

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20105%20800x450.jpg)



Thanks everyone for following along, and stay tuned for more...

Yogi

Title: Re: Freelance Inline Twin
Post by: steamer on March 25, 2017, 09:25:33 AM
I like the looks of that Yogi!     Coming right along!


Dave
Title: Re: Freelance Inline Twin
Post by: Perry on March 25, 2017, 12:45:34 PM
Hello Yogi, is that a Flexolap? If so how much undersize is the starting size vs nominal size and how much can it expand further?
Many thanks
Title: Re: Freelance Inline Twin
Post by: 90LX_Notch on March 25, 2017, 01:25:00 PM
Yogi it looks really great.  The cling wrap is a great idea.  I''m definitely going to use that one.

-Bob
Title: Re: Freelance Inline Twin
Post by: Brian Rupnow on March 25, 2017, 01:31:12 PM
Very nice engine build and documentation. I have never seen crankshaft bearings set up like that either. Does the shaft which the con rod ends ride on have a head on it that is locked between the bolted together end assemblies? How do you ensure that all 3 large sections of the crank that are bearing surfaces of the crank stay "aligned"?  ---Brian
Title: Re: Freelance Inline Twin
Post by: yogi on March 25, 2017, 11:32:41 PM
Thank you guys for the kind comments! It's very much appreciated.  :cheers:

Perry, the lap I'm using is an Acrolap. The one I have is about 0.05 mm under size. I don't know how far the lap will expand. I had one expanded about 0.2 mm over nominal. It started to get quite "barrel" shape, only cutting in the middle half of the lap. Not ideal, but it worked. They are brass, and can be turned down to whatever size you need.

Brian, the crank pin is locked between the outer crank disc assemblies, which are then located between the front and rear covers. This secures the whole crank assembly axial in the crankcase. The crank assembly is "self aligning". The disc assemblies are allowed to rotate on the crank pin to find their alignment, and once installed in the case, it can't move any more. I have a section view in the first post, that will help to illustrate. I hope I answered your question.

Thank you for your interest in my project,
Yogi

Title: Re: Freelance Inline Twin
Post by: Brian Rupnow on March 26, 2017, 12:03:56 AM
Very clever design, Yogi. I looked at that section view the first time around, and missed that.---Brian
Title: Re: Freelance Inline Twin
Post by: toolznthings on March 26, 2017, 12:57:11 AM
Looking good !  :ThumbsUp:
Title: Re: Freelance Inline Twin
Post by: yogi on April 20, 2017, 12:47:01 AM
Hello everyone, it's time for an update. Up next, the pistons:

I started with turning a boss to hold the blank in a collet for the subsequent operations. The piston diameter is 32mm, too large to go directly into a 5C collet.

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20106%20800x450.jpg)

Chucked in a collet, the OD is turned to finish size and the grooves for the rings are cut:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20107%20800x450.jpg)

Using a collet block, it is over to the mill to cut the recess for the connecting rod:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20108%20800x450.jpg)

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20109%20800x450.jpg)

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20110%20800x450.jpg)

Without removing the piston blank from the collet block, the cross hole is drilled and reamed. This ensures the hole is perfectly perpendicular to the milled recess.

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20111%20800x450.jpg)

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20112%20800x450.jpg)

The last operation is to turn off the chucking boss. The piston is clamped very gently in the 3 jaw chuck with some paper to protect the surface from getting marked up.

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20113%20800x450.jpg)

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20114%20800x450.jpg)

The finished Pistons:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20115%20800x450.jpg)


Thanks for following along, and stay tuned...
Yogi

Title: Re: Freelance Inline Twin
Post by: zeeprogrammer on April 20, 2017, 12:50:19 AM
I always dread seeing your posts Yogi. Your parts always look so...so...'finished'.  :ThumbsUp:
Title: Re: Freelance Inline Twin
Post by: Dave Otto on April 20, 2017, 01:02:32 AM
Nicely done Yogi!

Dave
Title: Re: Freelance Inline Twin
Post by: yogi on April 23, 2017, 03:00:56 PM
Thank you Dave and Zee for the kind comments! It's very much appreciated.  :cheers:

I have a number of components finished and felt it's time to assemble what I have. I don't want to get too far ahead of myself, making parts. If there is a problem, it would be easier addressed now rather than later. And it's always exiting to see an engine taking shape...

A plug is inserted in the camshaft bore to close it off on the back of the engine.

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20116%20800x450.jpg)

The crankshaft is finished up on the accessory end with a small diameter shaft extension.

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20117%20800x450.jpg)

The gear installed on the crankshaft:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20118%20800x450.jpg)

The connecting rods are assembled with the pistons and needle roller bearings:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20119%20800x450.jpg)

The assembled crankshaft is installed and the crankcase closed.

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20120%20800x450.jpg)

And the assembled engine block:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20121%20800x450.jpg)

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20122%20800x450.jpg)

To give you an idea of the size of the engine, here with yours truly.

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20123%20800x584.jpg)


I'm very pleased how the engine has turned out so far. Everything is fitting together and works the way I envisioned it when I designed it. I haven't discovered any design flaws (yet).  8)

Thank you for following along, and stay tuned for more.
Yogi


Title: Re: Freelance Inline Twin
Post by: Roger B on April 23, 2017, 05:46:07 PM
Looks wonderful  :praise2:  :praise2: What's the machine behind you in the last picture? CNC Deckel?
Title: Re: Freelance Inline Twin
Post by: stevehuckss396 on April 23, 2017, 09:56:58 PM
I agree, looks wonderful. Thanks for sharing.
Title: Re: Freelance Inline Twin
Post by: b.lindsey on April 23, 2017, 11:20:58 PM
Beautiful work Yogi!!  Nice to see your mug too  :D

Bill
Title: Re: Freelance Inline Twin
Post by: yogi on April 24, 2017, 12:45:00 AM
Thank you gentleman for the kind comments!  :cheers:

Roger, the machine is a Maho MH500 CNC mill.

Bill, I couldn't get the grin off of my face, so my wife made me post it...  :embarassed:
Title: Re: Freelance Inline Twin
Post by: Dave Otto on April 24, 2017, 12:45:11 AM
Very nice Yogi!

I really like the ball bearing supported crankshaft.


Dave
Title: Re: Freelance Inline Twin
Post by: yogi on April 25, 2017, 12:41:44 AM
Thank you Dave!

I'm very pleased how the crankshaft turned out. It's very low friction. I hope this will materialize in the running characteristic of the engine. I tried to take a short clip of me turning the engine over to demonstrate.
I have already ideas of future engines with this kind of crankshaft.

ps3SC21VXn0
Title: Re: Freelance Inline Twin
Post by: zeeprogrammer on April 25, 2017, 11:05:34 AM
 :ThumbsUp: Wow.

I saw the earlier picture of you. Nice to meet you.  ;D
Title: Re: Freelance Inline Twin
Post by: toolznthings on April 29, 2017, 05:03:00 PM
I'm up to date on your posts now. Great work as always !!  :ThumbsUp:
Title: Re: Freelance Inline Twin
Post by: gbritnell on April 29, 2017, 07:50:21 PM
Exceptional work! I'm following this build and getting some new ideas.
gbritnell
Title: Re: Freelance Inline Twin
Post by: yogi on May 12, 2017, 11:07:00 PM
Thank you gentlemen for the kind comments.  :cheers:

The next part for the engine I'll be making is the cylinder head.
I'll let the pictures do most of the talking but feel free to ask any questions.

Started with a facing cut:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20124%20800x450.jpg)

The outside contour is milled to full depth:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20125%20800x450.jpg)

Spotting and drilling:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20126%20800x450.jpg)

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20127%20800x450.jpg)

Milling the combustion chamber:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20128%20800x450.jpg)

Milling the recess for the O-ring sealing the coolant passage from the block to the head:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20129%20800x450.jpg)

Drilling and reaming for the valve guides:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20130%20800x450.jpg)

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20131%20800x450.jpg)

I'll be using Rimfire spark plugs. Since the reach is not long enough, the combustion chamber is getting an extension with a ball end mill:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20132%20800x450.jpg)

First side of the cylinder head complete:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20133%20800x450.jpg)

The cylinder head is turned over and faced to final thickness:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20134%20800x450.jpg)

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20135%20800x450.jpg)

The coolant passage is milled:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20136%20800x450.jpg)

The second side complete:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20137%20800x450.jpg)

The head is then set up on its side to drill the holes for mounting the exhaust manifold and carburetor mounting. The location for the inlet and exhaust ports are only spot drilled. They are angled and will be drilled later.

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20138%20800x450.jpg)

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20139%20800x450.jpg)


To be continued...

Title: Re: Freelance Inline Twin
Post by: 90LX_Notch on May 13, 2017, 02:27:58 AM
Nice.  Waiting for the continuation.


-Bob
Title: Re: Freelance Inline Twin
Post by: yogi on May 13, 2017, 03:58:57 AM
Thank you Bob!

To finish up the cylinder head, I needed the valve guides as the inlet and exhaust passages are drilled trough the guides.

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20140%20800x450.jpg)

Valve guides installed in the cylinder head (press fit):

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20141%20800x450.jpg)

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20142%20800x450.jpg)

The cylinder head is clamped in the vise at the correct angel using a bevel protractor.

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20143%20800x450.jpg)

The location of the hole is picked up with a center in the spot drilled location marked earlier.

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20144%20800x450.jpg)

Using an end mill, a flat is milled to be able to center drill and drill the hole on the angled surface.

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20145%20800x450.jpg)

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20146%20800x450.jpg)

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20147%20800x450.jpg)

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20148%20800x450.jpg)

The same process was then repeated three more times:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20149%20800x450.jpg)

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20150%20800x450.jpg)

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20151%20800x450.jpg)

To finish off the cylinder head, it needed a cover do seal the coolant passage.

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20152%20800x450.jpg)

The finished head assembly:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20153%20800x450.jpg)


Thank you all for following along and stay tuned for more...
Yogi



Title: Re: Freelance Inline Twin
Post by: Brendon M on May 15, 2017, 07:41:20 AM
Hello Yogi, it is looking great!
Title: Re: Freelance Inline Twin
Post by: fumopuc on May 15, 2017, 07:25:46 PM
Hi Yogi, I am still following quietly.
Title: Re: Freelance Inline Twin
Post by: toolznthings on May 16, 2017, 01:15:41 AM
Beautiful workmanship ! Great progress, too.  :cartwheel:

Brian
Title: Re: Freelance Inline Twin
Post by: Dave Otto on May 16, 2017, 01:27:37 AM
Hi Yogi
The cylinder head looks great!


Dave
Title: Re: Freelance Inline Twin
Post by: Art K on May 16, 2017, 03:38:20 AM
Yogi,
In just got caught cup on your most recent posts. All I can say is that it looks great. Still following along.
Art
Title: Re: Freelance Inline Twin
Post by: yogi on May 18, 2017, 05:34:54 AM
Thank you guys for the kind comments and following along. It's very much appreciated!  :cheers:

For the valves, I'm trying something new. Well, new to me, as it has been successfully done by other people before.

The valves are made up of two pieces and silver soldered together. With this method, the long, slender valve stem is already precision ground and doesn't need to be machined.

Before and after silver soldering:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20154%20800x450.jpg)

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20155%20800x450.jpg)

The valve head is finished:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20156%20800x450.jpg)

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20157%20800x450.jpg)

Last, the valve stem is turned to length and a groove for the spring retainer is cut:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20158%20800x450.jpg)

The finished valves:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20159%20800x450.jpg)


This method worked very well, and I can see me making valves this way in the future again.

Thank you for stopping by, and stay tuned for more...
Yogi




Title: Re: Freelance Inline Twin
Post by: Roger B on May 18, 2017, 07:36:42 AM
Still following along  :wine1: looking good  :praise2:  :praise2:
Title: Re: Freelance Inline Twin
Post by: Kim on May 19, 2017, 07:14:06 PM
Yogi, the valves look great!  And I like your method of fabricating vs just turning them down.
However, don't you have any problem with the rods going banana shaped during the soldering process?  How do you prevent that?
Kim
Title: Re: Freelance Inline Twin
Post by: yogi on May 20, 2017, 09:24:57 AM
Thank you for the kind comments Rodger and Kim.  :cheers:

Kim, to tell you the truth, I didn't really think about it. It's a good point though.

The valves are made out of O-1 drill rod. The reason I chose drill rod was because that's what I had that was precision ground. The solder I used was Easy-flo 45. Concentrating the heat to the large head part, being careful not to overheat the parts. I tried to get as little heat into the stem as possible.

I really don't have a good answer. Maybe I just got lucky...  :thinking:

Yogi
Title: Re: Freelance Inline Twin
Post by: Ian S C on May 20, 2017, 10:55:21 AM
The trick of keeping the valve stem cool while silver soldering is to stick it in a potato.
Ian S C
Title: Re: Freelance Inline Twin
Post by: steam guy willy on May 20, 2017, 12:30:18 PM
The trick of keeping the valve stem cool while silver soldering is to stick it in a potato.

Pink fir apple, Aliaser Craig or Marfona ??!!!!  Or even a baking one ..killing two birds with one stone !!
Title: Re: Freelance Inline Twin
Post by: yogi on May 21, 2017, 12:57:16 AM
Aha!!! A potato it is...  :ThumbsUp: :ThumbsUp: :ThumbsUp:
I will do that next time Ian.  8)
Title: Re: Freelance Inline Twin
Post by: b.lindsey on May 21, 2017, 01:41:53 AM
Still watching yogi, great looking parts and an inspirational project.

Bill
Title: Re: Freelance Inline Twin
Post by: Art K on May 21, 2017, 04:16:25 AM
Yogi,
Just out of curiosity in post #93 you show the valve guides they look like steel. What did you use?
Art
Title: Re: Freelance Inline Twin
Post by: yogi on May 21, 2017, 09:40:32 PM
Thank you guys for the compliments.  :cheers:

Art, the valve guides are made from O-1 drill rod.
Title: Re: Freelance Inline Twin
Post by: 90LX_Notch on May 21, 2017, 09:55:48 PM
Still following with keen interest yogi.

-Bob
Title: Re: Freelance Inline Twin
Post by: kuhncw on May 21, 2017, 11:00:03 PM
Yogi,

Very nice work on your inline twin.  I'm looking forward to hearing it run.

Chuck
Title: Re: Freelance Inline Twin
Post by: Brian Rupnow on May 22, 2017, 01:30:30 AM
I was thinking of the method you used for the valves yesterday, as I machined the valves from solid for my own current project. Something I read, and I'm not sure if I believe it or not. A well respected engine builder has stated that he doesn't try to get too accurate a fit between the valve stem and the guides. His explanation was that if you have a real high precision fit between the valve stem and the guides, then it doesn't allow the valve to "self center" on the seat and can lead to a poor valve seal on compression. His theory absolutely makes sense, but I have always tried for a precision fit on the engines I build. I'm sure there must be a "middle ground" in this theory. If the fit between stem and guide is too tight, then the valves will stick open and not seat at all. If the fit is too loose, then the engine will suck air around the guides, causing problems at idle. I read everything I can about designing and building engines, and I find his theory very interesting.---Brian
Title: Re: Freelance Inline Twin
Post by: yogi on May 22, 2017, 11:24:11 PM
Thank you guys for the kind comments.  :cheers:

Brian, making valves like I did, requires accurate equipment. Any runout in the collet will transfer to the valve and cause the valve face to not be concentric to the stem. As you mention, play in the valve guide could be used to compensate for that. Right now, my valve guides are a very close tolerance, and I'm planing on keeping it that way. I do foresee to lap the valves, as there probably is, even minimal, a little bit of runout. We have to see when it's assembly time if what I did worked or not.

I'll keep you posted.

Yogi
Title: Re: Freelance Inline Twin
Post by: yogi on June 13, 2017, 02:16:55 AM
Another part for the cylinder head is the bracket for the rockers.

First, I clamped a piece of stock vertical in the vise, to machine the contour and drill the the hole.

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20160%20800x450.jpg)

The work piece is laid horizontal to mill the bracket to finish width:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20161%20800x450.jpg)

The bracket is cut off the remaining stock with the cold saw:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20162%20800x450.jpg)

The last operation is to clean up the saw cut, milling the bracket to final thickness. Drilling the mounting holes, and tapping for a set screw that will hold the rocker shaft in place. The paper in the vise is to protect the finished surfaces from getting marked up.

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20163%20800x450.jpg)

The finished bracket:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20164%20800x450.jpg)


Stay tuned...
Yogi


Title: Re: Freelance Inline Twin
Post by: toolznthings on June 14, 2017, 01:37:11 AM
That came out real nice !  :ThumbsUp:

Brian
Title: Re: Freelance Inline Twin
Post by: Doc on June 14, 2017, 03:30:46 AM
You are doing sme nice work. I just found this build and am glad I did. some very nice work!!
I noticed your cnc the Maho Man I did a lot of driving one of those the one we had was a tool room machine with a b axis. Wish I would have bought it when they sold it. It went for I think 4500. Anyway I'm climbing aboard for the ride on the build keep up the nice work!!
Title: Re: Freelance Inline Twin
Post by: yogi on June 24, 2017, 12:34:04 AM
Thanks for the kind comments, Brian and Doc! It's very much appreciated!  :cheers:

For the camshaft, I'm staying with the spirit of this engine, as it will be built up of multiple pieces. In post 14 of this thread is a CAD rendering of the camshaft.

I started with the cam blanks, turned and parted off. They are made from 1144 Stressproof.

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20165%20800x450.jpg)

The second side of the cam blanks are finished turned:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20166%20800x450.jpg)

Drilled and tapped for a set screw:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20167%20800x450.jpg)

The two cam blanks, ready for the cam profile:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20168%20800x450.jpg)

To set up for the milling of the cam profile, I chucked up a piece of shaft in the collet block, and milled a flat for the set screw.

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20169%20800x450.jpg)

The collet block is set up vertical in the CNC mill and the cam blank secured with the set screw.

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20170%20800x450.jpg)

The profile is milled using a t-slot cutter, to cut both cams in the same program.

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20171%20800x450.jpg)

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20172%20800x450.jpg)

The process was then repeated for the second cam, except it is a mirrored version of the first one.

The two cams finished:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20173%20800x450.jpg)

The shaft has two flats milled, which need to be indexed 180 degrees. The collet block makes quick works of the indexing.

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20174%20800x450.jpg)

With the shaft still in the collet block, I engraved a line on the end of the shaft. This will help me to time the camshaft.

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20175%20800x450.jpg)

The assembled camshaft:

(http://i379.photobucket.com/albums/oo240/yogi107/Forum/Inline%20Twin%20176%20800x450.jpg)


to be continued...
Title: Re: Freelance Inline Twin
Post by: b.lindsey on June 24, 2017, 12:54:43 AM
Great progress and pictures both Yogi. Beautiful looking parts too.

Bill
Title: Re: Freelance Inline Twin
Post by: toolznthings on June 24, 2017, 01:35:44 AM
Nice with the t-slot cutter. Great thinking !  :ThumbsUp:

Brian
Title: Re: Freelance Inline Twin
Post by: gbritnell on June 24, 2017, 04:50:59 PM
Very nice work on the camshaft Yogi.
gbritnell
Title: Re: Freelance Inline Twin
Post by: Dave Otto on June 25, 2017, 01:01:40 AM
Great work on the bump stick Yogi.
Your parts always looks so nice!

Dave
Title: Re: Freelance Inline Twin
Post by: fumopuc on June 25, 2017, 04:21:07 AM
Hi Yogi, thanks for showing your Cam making prozess. It's comming together now.
Title: Re: Freelance Inline Twin
Post by: yogi on July 01, 2017, 02:17:01 AM
Thank you fine Gentlemen for the kind comments. It is always very much appreciated!  :cheers:

To finish up the gear train for the camshaft, I needed the idler gear. When I designed the engine, I utilized stock gears from SDP/SI. SDP has CAD files for all their gears for download on their site, which is a tremendous help in the design process.
For the idler gear, none of the stock gears would fit my application. My solution was to use a stock gear and modify it to my need.

To illustrate the design of the idler, and to adjust the backlash in the gears, I attached a CAD rendering below. The hole in the crankcase cover is drilled oversize, allowing some adjustment.

(http://i.imgur.com/XwgwrVh.jpg)

The stock gear, as received from SDP:

(http://i.imgur.com/H9sn2mc.jpg)

In the lathe, the gear was then bored out to the correct diameter for the miniature ball bearing.

(http://i.imgur.com/D3ezcXP.jpg)

(http://i.imgur.com/oEsMjak.jpg)

Parting off:

(http://i.imgur.com/exTbsPf.jpg)

A bushing is turned, to hold the bearings, and to mounted it to the crankcase cover.

(http://i.imgur.com/ErIXlkK.jpg)

The gear, bearing, and bushing assembled:

(http://i.imgur.com/GlF6cJT.jpg)

The idler installed on the engine:

(http://i.imgur.com/W2dTWfU.jpg)

The finished gear train, with the camshaft installed.
To note is the line engraved on the end of the camshaft as mentioned in an earlier post, for timing of the camshaft.

(http://i.imgur.com/thHLyhr.jpg)


Thank you all for following along, and stay tuned for more...
Yogi

Title: Re: Freelance Inline Twin
Post by: kuhncw on July 01, 2017, 03:35:05 AM
Nicely done, Yogi.  I like your solution for mounting the idler gear.

Great looking engine.  I'm looking forward to hearing it run.

Chuck
Title: Re: Freelance Inline Twin
Post by: crueby on July 01, 2017, 04:01:43 AM
Clever adjustment solution, gotta remember that one!   :ThumbsUp:
Title: Re: Freelance Inline Twin
Post by: Plani on July 02, 2017, 07:29:57 PM
Hi Yogi

This is a very nice looking geartrain! It's almost a shame to cover it up...
Did the gears come this way or did you blue them? They make a very nice contrast to the aluminum.


Plani


Title: Re: Freelance Inline Twin
Post by: yogi on July 03, 2017, 02:12:24 AM
Thank you guys for the nice comments!  :ThumbsUp: :ThumbsUp: :ThumbsUp:

Plani, I have to agree, it's almost a shame to cover it up...  8) 
and yes, the gears came from SDP blued like that.

Yogi
Title: Re: Freelance Inline Twin
Post by: toolznthings on July 03, 2017, 03:40:39 AM
Very nice, my friend !  :)

Brian
Title: Re: Freelance Inline Twin
Post by: Roger B on July 05, 2017, 08:38:14 AM
Still following along with interest  :ThumbsUp:  :ThumbsUp: I like your cam cutting technique with the T slot cutter  :praise2:
Title: Re: Freelance Inline Twin
Post by: yogi on July 27, 2017, 12:21:21 AM
Thank you Brian and Roger for the kind comments. It's very much appreciated!  :cheers:

The rocker arms are milled from 1144 stressproof steel. The process for making the rockers is the same I have used before on this engine using soft jaws.
The first side is machined:

(https://i.postimg.cc/Dyz7cDqP/Inline_Twin_186_800x450.jpg)

(https://i.postimg.cc/FszDssxX/Inline_Twin_187_800x450.jpg)

The soft jaws are set up for the second side:

(https://i.postimg.cc/BQv11mbd/Inline_Twin_188_800x450.jpg)

(https://i.postimg.cc/BQ6yjG0H/Inline_Twin_189_800x450.jpg)

Drilled and tapped the rocker for the lash adjustment screw:

(https://i.postimg.cc/X7qj4h1D/Inline_Twin_190_800x450.jpg)

The finished rockers:

(https://i.postimg.cc/SNsL6SjQ/Inline_Twin_191_800x450.jpg)

The rocker shafts are made as well:

(https://i.postimg.cc/TYwvMDNV/Inline_Twin_192_800x450.jpg)

For the adjustment screws, I modified a socket head cap screw be machining out the hex with a ball end mill.

(https://i.postimg.cc/DyzBydTz/Inline_Twin_193_800x450.jpg)

(https://i.postimg.cc/m2DkXhQq/Inline_Twin_194_800x450.jpg)

The adjustment screws installed:

(https://i.postimg.cc/ncrDg34n/Inline_Twin_195_800x450.jpg)


Stay tuned...
yogi
Title: Re: Freelance Inline Twin
Post by: 90LX_Notch on July 27, 2017, 12:41:40 AM
Those are nice looking rockers yogi.  I'm still following along.

-Bob
Title: Re: Freelance Inline Twin
Post by: b.lindsey on July 27, 2017, 12:43:56 AM
Great looking parts yogi. Still following here as well.  :ThumbsUp:

Bill
Title: Re: Freelance Inline Twin
Post by: Dave Otto on July 27, 2017, 12:56:19 AM
The rockers look great Yogi!
Cool idea on using the SHCSs for for the adjusters, nice tough material; it should hold up well.  :ThumbsUp:

Dave
Title: Re: Freelance Inline Twin
Post by: toolznthings on July 27, 2017, 01:41:01 AM
What can I say ..... :cartwheel:  :ThumbsUp:
Title: Re: Freelance Inline Twin
Post by: kuhncw on July 27, 2017, 02:49:00 AM
Very nice work Yogi.  I especially like your process for making rocker arms.

Chuck
Title: Re: Freelance Inline Twin
Post by: Plani on July 27, 2017, 10:05:25 AM
Very nice parts, Yogi  :ThumbsUp: :ThumbsUp: :ThumbsUp:
I especially like these soft jaws, very useful.

Plani
Title: Re: Freelance Inline Twin
Post by: Art K on July 28, 2017, 03:17:09 AM
Yogi,
Still following along. I like your valve train, the adjuster bolt is genius. I really like the rocker arms.
Art
Title: Re: Freelance Inline Twin
Post by: yogi on October 04, 2017, 04:03:28 AM
Thanks everybody for the kind comments! It's very much appreciated!  :cheers:

I didn't get as much done during the summer month as I'd hoped, but I still got a few bits and pieces done that I can share.

The flywheel is a straight forward turning job. First side done:

(https://i.postimg.cc/7Y6fLXZb/Inline_Twin_196_800x450.jpg)

Second side finished:

(https://i.postimg.cc/PrJSyzNw/Inline_Twin_197_800x450.jpg)

The finished flywheel:

(https://i.postimg.cc/c4HN3bYy/Inline_Twin_198_800x450.jpg)

As a contrast to the mostly aluminum engine, I decided to cold blue the flywheel. Hopefully this will also help a little with corrosion protection.
I used Brownells Oxpho Blue. I haven't done any cold blue before, and I'm happy how it turned out. It's not as dark as a commercial black oxide finish, and has more of a blue tint to it.

(https://i.postimg.cc/fTb854BC/Inline_Twin_199_800x450.jpg)

The flywheel installed on the crankshaft using a locking assembly.

(https://i.postimg.cc/MKG6zTpS/Inline_Twin_200_800x450.jpg)

While I was bluing the flywheel, I decided to give the rockers the same treatment:

(https://i.postimg.cc/15zqbyxg/Inline_Twin_201_800x450.jpg)

The rockers installed:

(https://i.postimg.cc/hPj63QpH/Inline_Twin_202_800x450.jpg)

I also made the tappets and tappet guides:

(https://i.postimg.cc/tCTNH30N/Inline_Twin_203_800x450.jpg)

(https://i.postimg.cc/02jmM9yY/Inline_Twin_204_800x450.jpg)

(https://i.postimg.cc/65q6L3RQ/Inline_Twin_205_800x450.jpg)

Valve springs and spring retainers installed:

(https://i.postimg.cc/pXrny8bQ/Inline_Twin_206_800x450.jpg)

Push rods installed:

(https://i.postimg.cc/gkjNdngQ/Inline_Twin_207_800x450.jpg)


Hopefully with the days getting shorter and the temperatures cooler, I'll be getting more quality time in the shop and progress on the engine.

Thanks everyone for following along, and stay tuned for more...


Title: Re: Freelance Inline Twin
Post by: Roger B on October 04, 2017, 07:07:04 AM
Looking good  :praise2:  :praise2: I do like the bluing  :ThumbsUp: Not too long until the first pops.
Title: Re: Freelance Inline Twin
Post by: b.lindsey on October 05, 2017, 01:16:51 AM
Great to see an update yogi!!  The bluing looks very nice and provides contrast as you said. I like it!!

Bill
Title: Re: Freelance Inline Twin
Post by: Dave Otto on October 05, 2017, 01:27:51 AM
Nice update and progress Yogi.

Are you using a hot or cold process for the blueing? You may have said before but I can recall.
Beautiful work on all the new parts!

Dave
Title: Re: Freelance Inline Twin
Post by: Art K on October 05, 2017, 02:50:06 AM
Yogi,
I am curious about the flywheel mounting set up. Is that some sort of taper lock setup? Could you define how that is arranged.
Art
Title: Re: Freelance Inline Twin
Post by: 90LX_Notch on October 05, 2017, 11:46:00 PM
Wow, it is looking really good yogi.

-Bob
Title: Re: Freelance Inline Twin
Post by: yogi on October 06, 2017, 05:36:30 AM
Thank you guys for the compliments! It is very much appreciated  :cheers:

Dave, the blueing is a cold process. I used Brownells oxpho blue.

Art, it is a tapered bushing, like you said. A few thoughts of why I choose to go this route: All that's required, is a reasonably accurate shaft and bore. It will also guarantee a wobble free flywheel. The engine is quite "industrial" looking, so I felt I could get away with it...  8)

See here for my source: http://info.maedler.de/product/1643/1621/spannsaetze-bar-bohrung-5-bis-100-mm


Yogi



Title: Re: Freelance Inline Twin
Post by: Plani on October 09, 2017, 09:32:04 AM
That looks awesome, Yogi  :ThumbsUp: :ThumbsUp: :ThumbsUp:
Can't wait for the first pops. I guess it can't be too long anymore....

Plani
Title: Re: Freelance Inline Twin
Post by: cfellows on October 09, 2017, 06:23:11 PM
That's one nice engine.  Nice design, very nicely machined and finished.  I like the industrial look of it.

Chuck
Title: Re: Freelance Inline Twin
Post by: yogi on October 15, 2017, 04:23:57 PM
Thank you gentlemen for the kind comments!  :cheers:

For the carburetion, I'm planing on using a RC engine carburetor. To mount it to the engine, I need to build a flange.

Holding a long piece of aluminum in the vise, the first side is milled:

(https://i.postimg.cc/BQbVVXLL/Inline_Twin_208_800x600.jpg)

The stock is turned over, and the second side is finished:

(https://i.postimg.cc/BQ6JBTxd/Inline_Twin_209_800x600.jpg)

The "holding stock" is cut off on the cold saw:

(https://i.postimg.cc/c4JRSzS6/Inline_Twin_210_800x600.jpg)

The saw cut is cleaned up, and the holes drilled:

(https://i.postimg.cc/8PcRSvbG/Inline_Twin_211_800x600.jpg)

(https://i.postimg.cc/hPGjvWhW/Inline_Twin_212_800x600.jpg)

The finished flange:

(https://i.postimg.cc/RV0DDGpL/Inline_Twin_213_800x600.jpg)


Stay tuned...
Yogi


Title: Re: Freelance Inline Twin
Post by: yogi on October 15, 2017, 09:48:08 PM
...and the O.S. carburetor installed:

(https://i.postimg.cc/02QKxbpw/Inline_Twin_214_800x600.jpg)


Next, wroooooom...
Stay tuned.

Yogi




Title: Re: Freelance Inline Twin
Post by: b.lindsey on October 15, 2017, 11:20:51 PM
Got my ears on Yogi. Waiting for the nice sounds of a new runner. Very nice work.

Bill
Title: Re: Freelance Inline Twin
Post by: Art K on October 16, 2017, 12:08:06 AM
Yogi,
the intake manifold looks great. Still following along.
Art
Title: Re: Freelance Inline Twin
Post by: kuhncw on October 16, 2017, 01:22:57 AM
Yogi,

Thanks for posting such an educational build log.

You are doing a great job on a very nice "industrial style" engine.  I like the look.

Chuck
Title: Re: Freelance Inline Twin
Post by: yogi on October 17, 2017, 12:29:01 AM
Thank you guys for the kind comments!  :cheers:


We have the first pop!   :whoohoo:

Having all the parts needed to see if there is life in this engine, I set up the ignition and fuel temporarily and gave it a spin. There is still some tuning needed of course, but without a cooling system, I kept the runs short to not overheat the engine.

A few short videos of the first runs:

Vjz0GZ9cvlg
wp37u8pznbo
mn_B0axZ1GM

Thanks everyone for following along, and stay tuned for more...
Yogi

Title: Re: Freelance Inline Twin
Post by: toolznthings on October 17, 2017, 01:01:34 AM
Hi Yogi,

Could expect no less from the design and craftsmanship. No doubt in my mind that it would not run ! :cartwheel:

Brian
Title: Re: Freelance Inline Twin
Post by: Dave Otto on October 17, 2017, 02:07:37 AM
Congrats on the first pops Yogi!
She sounds great!


Dave
Title: Re: Freelance Inline Twin
Post by: Art K on October 17, 2017, 02:30:51 AM
Yogi,
Sounds great, a little fine tuning but wonderful it runs.
Art
Title: Re: Freelance Inline Twin
Post by: 90LX_Notch on October 17, 2017, 02:55:00 AM
Very nice yogi.  It sounds great.  Congratulations.

-Bob
Title: Re: Freelance Inline Twin
Post by: Longboy on October 17, 2017, 05:42:37 AM
Runs and sounds like its all business. Great build!    Dave
Title: Re: Freelance Inline Twin
Post by: Plani on October 17, 2017, 07:08:44 AM
Congratulations on the first pops, Yogi :whoohoo:
It's runnig great  :ThumbsUp: :ThumbsUp: :ThumbsUp:

Plani
Title: Re: Freelance Inline Twin
Post by: rudydubya on October 17, 2017, 07:11:03 AM
Nicely done Yogi.  I like the sound.  Thanks for sharing your build.

Regards,
Rudy
Title: Re: Freelance Inline Twin
Post by: kuhncw on October 17, 2017, 08:15:51 PM
Nicely done, Yogi.  Your twin sounds like a strong runner and should sound even stronger when you add exhaust stacks.


Chuck
Title: Re: Freelance Inline Twin
Post by: Ye-Ole Steam Dude on October 17, 2017, 09:41:25 PM
Love that sound.

Thomas
Title: Re: Freelance Inline Twin
Post by: Roger B on October 17, 2017, 09:49:52 PM
Looks and sounds good  :praise2:  :praise2: What are you using for fuel?
Title: Re: Freelance Inline Twin
Post by: Rustkolector on October 18, 2017, 02:31:22 AM
Yogi,
Nicely done, and you got the slow idle without a large flywheel. Congratulations. I have a question that goes back to the design of this engine. You did not include any splash connecting rod dippers to disperse oil to the rods or upper interior sections of the engine. What are you counting on to get adequate splash lubrication to the interior moving parts?

Jeff
Title: Re: Freelance Inline Twin
Post by: yogi on October 18, 2017, 12:35:48 PM
Thanks everyone for the compliments!!! It is very much appreciated!  :cheers:

Roger, I'm running on Coleman fuel.

Jeff, the oil level is set that the rod ends just barely dip into the oil and provide the splash for the upper components. The crankcase is just open at this time where the breather will be installed. Judging by the amount of oil spewing out through the port, I feel the lubrication is more then adequate.

Since we are talking about oil, I decided to use a bit of a lighter oil then the regular 30 weight engine oil. I'm using Mobil DTE 26 (ISO 68) as that's what I'm using in my machine tools. I'm not using regular engine oil because of all the additives in these oils now a days. If anybody has some thought on this, or anything else about the engine, I would like to hear it.

Thanks for following a long and stay tuned for more...
Yogi

Title: Re: Freelance Inline Twin
Post by: ShopShoe on October 18, 2017, 01:49:13 PM
Congratulations on a very nice runner. I like the sound as well.

--ShopShoe
Title: Re: Freelance Inline Twin
Post by: ThomasM on October 18, 2017, 03:54:00 PM
Congratulations for this engine !

When i first saw your crankshaft with the parallel moving pistons and therefore the equal firing order i was wondering if a 180 offset and unequal firing would sound better.
Now i know that i was wrong.
The engine sounds fantastic and the clean technical look is also perfect.

Best regards,
Thomas
Title: Re: Freelance Inline Twin
Post by: Rustkolector on October 18, 2017, 07:01:37 PM
Yogi,
It sounds like youíre getting reasonable splash in your crankcase. Regarding oil type, in my opinion engine oils are better for model engines than machine and hydraulic oils. My particular concern with the latter oils in 4 stroke model engines would be crankcase moisture retention in wet sump designs. Keep in mind our engines never get up to normal engine operating temps so ~30 degrees above ambient is all you can expect in a model engine crankcase. Moisture production and retention is significant especially when the engine is new. Machine and hydraulic oils are formulated to allow water and crud to drop out and be retained in the engine. Engine oils provide detergents and water dispersants to keep crud and water in suspension allowing it to be observed (turns milky) and easily removed by draining.

Regarding oil viscosity, I built a slow speed engine that allowed me to install Plexiglas inspection covers on both sides of the engine to observe oil splash vs RPM. As you might expect, 5w-20 engine oil splashed better than 10W-30, which did better than SAE 20, etc., so the lower viscosity the better in my experience. Also, oil surface tension in a cool running oil system becomes a significant factor when evaluating effectiveness of a small splash system.

I just finished a 180 degree slow speed twin. I am getting quite fond of its John Deerish sound and I especially like the lack of heavy crankcase pressure pulsations. Watch out for the latter in the 360 degree crank design. A check valve design breather to control pressure is almost mandatory.

Jeff
Title: Re: Freelance Inline Twin
Post by: yogi on October 18, 2017, 10:04:15 PM
Thanks for the compliments, guys!  :cheers:

Jeff, good input on the oil. Thank you! I will take that into consideration.
I was contemplating a 180 degree crank for a while, but then settled on the 360 crank. I'm sure that would really sound cool too...


Yogi



Title: Re: Freelance Inline Twin
Post by: Art K on October 19, 2017, 12:43:35 AM
Yogi,
I read your bit about using ISO 68 which I recognized as hydraulic oil. I wouldn't personally use it in place of motor oil and thankfully Jeff gave a very definitive reason why.
Art
Title: Re: Freelance Inline Twin
Post by: fumopuc on October 29, 2017, 07:53:55 PM
Hi Yogi, I am late to the party, nice sound. Congratulations for this well made engine.
Title: Re: Freelance Inline Twin
Post by: yogi on March 29, 2018, 09:22:58 PM
Progress on the engine has been painfully slow, but I finally have some parts to share.  :atcomputer:

Next, I'll be working on the cooling system, staring with the pump.

I started with some gear stock, parting off two blanks.

(https://i.postimg.cc/9XsYCgfR/Inline_Twin_215_800x600.jpg)

To ensure both gears are exactly the same width and flat, Brian (toolznthings) helped me out with his surface grinder.

(https://i.postimg.cc/CxsGCFsk/Inline_Twin_216_800x600.jpg)

(https://i.postimg.cc/wx1kKY9Y/Inline_Twin_217_800x600.jpg)

The finished gears, with the shaft installed.

(https://i.postimg.cc/wBF1MMc4/Inline_Twin_218_800x600.jpg)

The pump housing is milled from bronze.

(https://i.postimg.cc/zfqLqKWR/Inline_Twin_219_800x600.jpg)

(https://i.postimg.cc/fLLJ9s8z/Inline_Twin_220_800x600.jpg)

(https://i.postimg.cc/7Z3GvmCk/Inline_Twin_221_800x600.jpg)

... so is the rear cover...

(https://i.postimg.cc/fLrk7PPx/Inline_Twin_222_800x600.jpg)

(https://i.postimg.cc/w3KvZmgM/Inline_Twin_223_800x600.jpg)

The finished pump housing parts:

(https://i.postimg.cc/SRYRgr0H/Inline_Twin_224_800x600.jpg)

With the gears installed.

(https://i.postimg.cc/FH4bJf3h/Inline_Twin_225_800x600.jpg)

And the pump installed on the engine.

(https://i.postimg.cc/fTXjL73H/Inline_Twin_226_800x600.jpg)


Thanks for following a long and stay tuned for more...
Yogi


Title: Re: Freelance Inline Twin
Post by: Perry on March 29, 2018, 11:03:15 PM
Great looking parts yogi. I've used J. Howells design of magnetic driven impeller water pump on mine twin engine.

Regards Perry
Title: Re: Freelance Inline Twin
Post by: kuhncw on March 29, 2018, 11:11:16 PM
Yogi,

Very nice job on the pump.

Thanks for the update.

Chuck
Title: Re: Freelance Inline Twin
Post by: Art K on March 30, 2018, 02:51:45 AM
Yogi,
Great to see progress. I haven't made a water cooled engine, so haven't needed to struggle with the idea of impeller or gear. What were you planning for the radiator?
Art
Title: Re: Freelance Inline Twin
Post by: toolznthings on March 30, 2018, 10:18:36 PM
Thanks for the honorable mention ! It's about time you got something done !  :stickpoke:

Pump came out super nice !
Title: Re: Freelance Inline Twin
Post by: Dave Otto on March 31, 2018, 01:11:13 AM
Nice work on the pump Yogi, it looks great!


Dave
Title: Re: Freelance Inline Twin
Post by: Rustkolector on March 31, 2018, 04:32:49 AM
Yogi,
Great project and nice looking pump. What type of shaft seal are you using in the pump?

Jeff
Title: Re: Freelance Inline Twin
Post by: Brian Rupnow on March 31, 2018, 01:48:10 PM
Very impressive engine. Looks great and runs great. Congratulations.---Brian
Title: Re: Freelance Inline Twin
Post by: yogi on March 31, 2018, 05:20:45 PM
Thank you everyone for the kind comments! It's very much appreciated.  :cheers:

Art, the jury is still out on the radiator design. I'm contemplating either a built up bar stock radiator inspired by Jerry Howell's design, or a PC cooler radiator. Right now I'm leaning towards the PC radiator. Stay tuned, I guess...  ;)

Jeff, I'll use a O-ring for the shaft seal in the pump.


Yogi
Title: Re: Freelance Inline Twin
Post by: kuhncw on March 31, 2018, 10:51:58 PM


Hi Yogi,

What is the diametral pitch of your pump gears and what size shaft did you use?

Also, how did you cut the blind holes in the pump body.  I'm guessing you plunge cut them with an end mill?

Thanks.

Chuck
Title: Re: Freelance Inline Twin
Post by: Art K on March 31, 2018, 11:57:14 PM
Yogi,
I have to admit to me the path of least resistance would be not making it myself, thus the computer radiator sounds like a great idea.
Art
Title: Re: Freelance Inline Twin
Post by: Rustkolector on April 01, 2018, 01:25:59 AM
Yogi,
I vote for the Jerry Howell design radiator, but only for its great looks. The 120mm computer radiators will get rid of a lot of heat with little air flow. I have three engines using them. Regarding your pump seal, I have built 5 of Jerry Howell's brass gear pumps. On the first three I used a standard O-ring behind the driven gear. All three leaked to some degree. Jerry said he used an O-ring out of a Bic butane lighter and it never leaked. In my case one leaked pretty quickly, the other two leak but to varying degrees at different times (?). The last two pumps were built with lip type oil seals and have not leaked a drop. I since learned that O-rings can be used for rotary seals but require a harder material, and they should be installed in a close tolerance full O-ring groove. The latter requirement was beyond my skill level on .125" dia. shaft bores. I have recently replaced my worst leaker with a new pump and lip seal. No leaks so far. The only problem I find with the lip seals is that they are a bit expensive.
Jeff 
Title: Re: Freelance Inline Twin
Post by: Zephyrin on April 01, 2018, 08:49:25 AM
Thanks for this instructive thread Yogi, amazing level of skill, and a beautiful engine.

Rustkolector:
I do have a similar experience with leaks on 3 tiny water pumps I did, all fitted with plain O ring...thanks for suggesting oil lip seals!
Title: Re: Freelance Inline Twin
Post by: Plani on April 01, 2018, 12:29:19 PM
That's a beautyful looking pump, Yogi  :ThumbsUp: :ThumbsUp: :ThumbsUp:

Plani
Title: Re: Freelance Inline Twin
Post by: yogi on April 01, 2018, 01:50:32 PM
Thank you guys for the comments!  :cheers:

Chuck, the gear is 10 Teeth, 24 D.P., 14.5į Pressure Angle. The shaft diameter is 4mm. The blind hole is milled to size with a circular interpolation on the CNC mill.

Jeff, thank you very much for the information on sealing your pumps. I will definitely take that into consideration. Where do you source lip seals, as small as we use?

Regarding the radiator, I agree with both of you, Art and Jeff. I like the fact that the computer radiator will be much less work, but the looks of the Howell radiator is hard to beat.


Thank you all for the input,
Yogi

 
Title: Re: Freelance Inline Twin
Post by: Roger B on April 01, 2018, 02:56:56 PM
Excellent Pump  :praise2: I am just about to start on the water pump for my twin. This will use Delrin gears which removes any corrosion problems but does require a little more clearance to allow for thermal expansion.
For the last pump I was able to source 6mm bore 10mm OD 2mm thick lip seals from a normal bearing supplier. The same supplier also offers 4mm bore but somewhat more expensive.
Title: Re: Freelance Inline Twin
Post by: yogi on April 01, 2018, 03:15:08 PM
Thanks Roger!

I already found small lip seals and ordered a couple. I just wasn't looking in the right place.  :atcomputer:
With 4mm ID 8mm OD and 2mm wide, the seal is not much bigger than a O-ring. Modifying the pump housing to accept the seal will be easy.

Thanks everyone for the input!
Yogi

Title: Re: Freelance Inline Twin
Post by: kuhncw on April 02, 2018, 03:17:01 AM
"Chuck, the gear is 10 Teeth, 24 D.P., 14.5į Pressure Angle. The shaft diameter is 4mm. The blind hole is milled to size with a circular interpolation on the CNC mill."

Yogi, 

Thanks for the pump gear information.  I'd not thought of milling the blind holes as they are so small.  I'll give that a try, now that my Taig mill has ball screws.

Chuck
Title: Re: Freelance Inline Twin
Post by: yogi on October 11, 2018, 08:10:47 PM
With a crazy busy summer at work, progress on the engine has been virtually non existent.
I was finally able to spend some time in the workshop this week, and can show some progress. Work continues on the cooling system.

First order of business was to modify the pump housing to accept a lip seal, as suggested by Jeff above.

(https://i.postimg.cc/fW0DR0bK/Inline-Twin-227-800x600.jpg)

Before and after installation of the lip seal:

(https://i.postimg.cc/c4RWQywt/Inline-Twin-228-800x600.jpg)

(https://i.postimg.cc/8zTS4KmK/Inline-Twin-229-800x600.jpg)


Next, I made the plumbing to connect the pump output to the cylinder block passage.
Milling the fitting to the cylinder block:

(https://i.postimg.cc/BQ9sLQLG/Inline-Twin-230-800x600.jpg)

(https://i.postimg.cc/5yvV7DrG/Inline-Twin-231-800x600.jpg)

(https://i.postimg.cc/rwgLP1h8/Inline-Twin-232-800x600.jpg)


The original plan was to bend tubing from the pump to the inlet fitting, but that was an utter failure due to the small radius in my design. As solution, I made an elbow to be able to make the corner around the cylinder block.

(https://i.postimg.cc/QMtrGFPc/Inline-Twin-233-800x600.jpg)

(https://i.postimg.cc/Xvz6VVSm/Inline_Twin_234_(800x600).jpg)

(https://i.postimg.cc/sxFFhw2J/Inline_Twin_235_(800x600).jpg)

(https://i.postimg.cc/3R05NP3R/Inline_Twin_236_(800x600).jpg)

(https://i.postimg.cc/d3Gbmrkc/Inline_Twin_237_(800x600).jpg)

The finished elbow

(https://i.postimg.cc/Hs9Gr01Q/Inline_Twin_238_(800x600).jpg)

The plumbing installed on the engine:

(https://i.postimg.cc/L4fFpKyQ/Inline_Twin_239_(800x600).jpg)



Thanks everyone for their patience following along, and stay tuned for more...

Yogi




Title: Re: Freelance Inline Twin
Post by: Roger B on October 11, 2018, 08:15:06 PM
Glad to see you back on this one  :ThumbsUp:  :ThumbsUp: I have a similar problem with the connection from my water pump to the cylinder block  :headscratch:
Title: Re: Freelance Inline Twin
Post by: Ye-Ole Steam Dude on October 11, 2018, 09:08:14 PM
Hello Yogi,

Nice update and glad to see you back in the shop.

Have a great day,
Thomas
Title: Re: Freelance Inline Twin
Post by: toolznthings on October 12, 2018, 01:05:10 AM
I like it !  :cartwheel:  :cartwheel: Nice work.  :ThumbsUp:
Title: Re: Freelance Inline Twin
Post by: Rustkolector on October 12, 2018, 02:41:40 AM
Yogi,
In looking at your photo of the water pump housing with the seal installed, you have the seal in backwards. The lips should be on the liquid side. Maybe you already knew this. I thought I would mention it just in case.
Jeff
Title: Re: Freelance Inline Twin
Post by: Art K on October 12, 2018, 03:51:02 AM
Yogi,
Glad to see you are making progress again. I have a friend in tool & die he is crazy busy as well.
Art
Title: Re: Freelance Inline Twin
Post by: yogi on October 12, 2018, 05:28:54 PM
Thanks guys for the kind comments, it's very much appreciated.

Jeff, Oh boy, I sure wasn't paying attention. Thanks for pointing it out.

Art, I'm glad to hear your friend is busy. That's much better then the opposite. I don't work in the metal industry any more, not that the aviation industry is any less stressful though...  :thinking:


Yogi


Title: Re: Freelance Inline Twin
Post by: Plani on October 16, 2018, 07:09:26 AM
Nice pictures and progress on the pump  :ThumbsUp:
Looking forward to some extended runs with the cooling system up and running.

Plani
Title: Re: Freelance Inline Twin
Post by: yogi on October 26, 2018, 09:47:10 PM
To make the connection from the coolant outlet passage on the cylinder head to a radiator hose, I needed to make a fitting. I took the inspiration for this fitting from a thermostat housing.

The fitting is made of two parts:

(https://i.postimg.cc/K8G6BKmC/Inline_Twin_240_(800x600).jpg)

To assemble the two parts, slight press fit and some JB Weld for good measure.

(https://i.postimg.cc/8PSQkK9p/Inline_Twin_241_(800x600).jpg)

...and the fitting installed on the engine:

(https://i.postimg.cc/VkK3RY6v/Inline_Twin_242_(800x600).jpg)


The next set of parts I made were the pulleys to drive the pump. I'll be using two O-Rings as drive belts.

(https://i.postimg.cc/N0VS3pRw/Inline_Twin_243_(800x601).jpg)

(https://i.postimg.cc/NMHSBmx2/Inline_Twin_244_(800x599).jpg)

The bearings installed in the pump pulley.

(https://i.postimg.cc/KY4CpdkN/Inline_Twin_245_(800x600).jpg)

The pulley installed on the pump:

(https://i.postimg.cc/MTgwYz9V/Inline_Twin_246_(800x600).jpg)


At this point is was time for a test run. I used a pulley I messed up earlier and had to remake, chucked up in my drill motor to drive the pump. I measured the rpm at about 750.

SiWmZvKZua8

Thanks everyone for following along, and stay tuned for more.

Yogi
Title: Re: Freelance Inline Twin
Post by: Ye-Ole Steam Dude on October 26, 2018, 11:00:03 PM
Hello yogi,

Beautiful work as usual and that pump works great.

Have a great day,
Thomas
Title: Re: Freelance Inline Twin
Post by: kuhncw on October 27, 2018, 12:01:44 AM
Hi Yogi,

Very nice work on the pump and piping.  Good looking design.

Chuck
Title: Re: Freelance Inline Twin
Post by: toolznthings on October 27, 2018, 01:12:09 AM
Coming along great !!  :cartwheel:
Title: Re: Freelance Inline Twin
Post by: 10KPete on October 27, 2018, 07:25:45 AM
Neat, sweet and petite !!  I some how missed a big span of posts and just now caught up. Excellent work.

 :cheers:

Pete
Title: Re: Freelance Inline Twin
Post by: fumopuc on October 28, 2018, 05:37:36 PM
Hi Yogi, nice progress. Nice to see it doing what it should do. Something what I will attack also soon.
Title: Re: Freelance Inline Twin
Post by: yogi on November 15, 2018, 09:47:56 PM
Thanks guys for the kind comments! It's very much appreciated.

To have a way to tension the O-ring belts, I decided to build a dummy alternator.

For the alternator bracket and tensioner parts, which are somewhat odd shaped, the first side is machined. Then a set of machinable jaws are installed in the vise to machine off the holding stock and finish the second side.

(https://i.postimg.cc/9QPcB0WM/Inline_Twin_247_(800x600).jpg)

(https://i.postimg.cc/9QHWTZHK/Inline_Twin_248_(800x600).jpg)

(https://i.postimg.cc/DzBFtN43/Inline_Twin_249_(800x600).jpg)

Second side in the soft jaws:

(https://i.postimg.cc/qRq00G2h/Inline_Twin_250_(800x600).jpg)

(https://i.postimg.cc/prnH5XGP/Inline_Twin_251_(800x600).jpg)

(https://i.postimg.cc/QtzDMWq6/Inline_Twin_252_(800x600).jpg)

The tensioner parts are tapped, and the slot is milled for the fork.

(https://i.postimg.cc/fbwDqsLv/Inline_Twin_253_(800x600).jpg)

(https://i.postimg.cc/7PpCsCyM/Inline_Twin_254_(800x600).jpg)

The alternator housing and end bell are finish machined:

(https://i.postimg.cc/SjFp6F3C/Inline_Twin_255_(800x600).jpg)

(https://i.postimg.cc/jqWw4HBS/Inline_Twin_256_(800x600).jpg)

Here the finished parts:

(https://i.postimg.cc/wjz1zSM1/Inline_Twin_257_(800x600).jpg)

(https://i.postimg.cc/KYv4kBnF/Inline_Twin_258_(800x600).jpg)

(https://i.postimg.cc/3xZdxn0n/Inline_Twin_259_(800x600).jpg)

(https://i.postimg.cc/Dzj0q0gG/Inline_Twin_260_(800x600).jpg)

and the assembled alternator:

(https://i.postimg.cc/8PM7q1p8/Inline_Twin_261_(800x600).jpg)

(https://i.postimg.cc/6383zKjm/Inline_Twin_262_(800x600).jpg)

installed on the engine:

(https://i.postimg.cc/rm7pPH7F/Inline_Twin_263_(800x600).jpg)

(https://i.postimg.cc/fT9zJ5pY/Inline_Twin_264_(800x600).jpg)


Thanks for following along, and stay tuned.
Yogi

Title: Re: Freelance Inline Twin
Post by: Rustkolector on November 16, 2018, 04:45:30 AM
Hi Yogi,
Your Twin is turning out very nicely. Looking forward to see it in its completed form. You may still have time to finish it up for Cabin Fever in January. Hope you plan to have it at the show. Even if you don't get it finished, bring it along anyway.
Jeff
Title: Re: Freelance Inline Twin
Post by: Dave Otto on November 16, 2018, 01:53:52 PM
Beautiful work Yogi!

Dave
Title: Re: Freelance Inline Twin
Post by: toolznthings on November 16, 2018, 01:57:30 PM
Super nice !   :cartwheel:
Title: Re: Freelance Inline Twin
Post by: kuhncw on November 17, 2018, 06:32:54 PM
Nicely done,  Yogi.

Functional, yet adds a lot to the look.

Chuck
Title: Re: Freelance Inline Twin
Post by: Roger B on November 17, 2018, 07:28:37 PM
Looks good  :praise2: The next challenge is a working generator or alternator  :stir:  :) I think that the alternator might be easier without a commutator  :headscratch:
Title: Re: Freelance Inline Twin
Post by: Art K on November 17, 2018, 08:35:02 PM
Yogi,
The "thermostat" housing looks great, clean & elegant. The alternator bracket looks good as well. I assume you need to remove an end to tighten it? Or did you complicate it by left handed threads on one end and wrench flats in the middle. Everything looks great glad to see you back at it.
Art
Title: Re: Freelance Inline Twin
Post by: yogi on November 19, 2018, 01:01:58 PM
Thank you guys for the kind comments! It's very much appreciated!  :cheers:

Jeff, no guaranies about Cabin Fever, but that would be a goal to work towards...

Roger,  :stickpoke: :thinking: :stir:

Art, yes, I have to remove one side to adjust the tensioner. I certainly contemplated a right/left hand thread like a turnbuckle, but decided against it for simplicity sake.


Yogi


Title: Re: Freelance Inline Twin
Post by: Craig DeShong on December 06, 2018, 11:50:29 PM
How have I missed this thread till now  :-[

You've built a little Jem Yogi  :cheers:
Title: Re: Freelance Inline Twin
Post by: Brian Rupnow on December 07, 2018, 12:09:57 AM
A very class act Yogi. Beautiful engine.---Brian
Title: Re: Freelance Inline Twin
Post by: kuhncw on January 21, 2019, 02:06:43 AM
Yogi, where did you buy the 4 X 8 X 2 lip seals for your coolant pump?

Thanks.

Chuck
Title: Re: Freelance Inline Twin
Post by: scc on January 21, 2019, 10:04:29 AM
An extremely nice engine Yogi,  Good job!     Terry
Title: Re: Freelance Inline Twin
Post by: yogi on January 21, 2019, 12:51:23 PM
Thank you guys for the compliments! It's very much appreciated.  :cheers: :cheers: :cheers:

Chuck, I found the lip seals at Grainger.
https://www.grainger.com/product/DDS-Single-Lip-Rotary-Shaft-Seal-52VZ39


Yogi

Title: Re: Freelance Inline Twin
Post by: kuhncw on January 21, 2019, 03:48:05 PM
Yogi,

Thanks for the source for the 4mm seal.

Regards,

Chuck
Title: Re: Freelance Inline Twin
Post by: yogi on March 13, 2019, 08:40:31 PM
Alright, I have another part to add to the engine, as I still work on the cooling system.

The fan is made from .040" 3003 aluminum sheet. I used CA glue and masking tape to secure the sheet to a plate. The use of masking tape seems to be popular by a number of YouTube machinist, so I figured I would give it a try. It worked very well. To release, I warmed up the parts until the bond let go.

(https://i.postimg.cc/4yB5ZcQh/Inline_Twin_265_(800x600).jpg)


The fan blade after deburring:

(https://i.postimg.cc/Hsv2hQLq/Inline_Twin_266_(800x600).jpg)


To press the radius into the blades, I 3d printed a die with the required shape. This was an experiment, and it worked flawless. I'm certain this would work on even thicker material.

(https://i.postimg.cc/QdBbGH9H/Inline_Twin_267_(800x600).jpg)

(https://i.postimg.cc/G3Qzk0nh/Inline_Twin_268_(800x600).jpg)

(https://i.postimg.cc/yY8jjf7h/Inline_Twin_269_(800x600).jpg)


The last part was to twist the blades. For this, I used the bending die again, to gripped the blade firmly, while using a protractor to twist each blade the same amount.

The finished fan:

(https://i.postimg.cc/0yLC8PDZ/Inline_Twin_270_(800x600).jpg)

(https://i.postimg.cc/PxHzwy6w/Inline_Twin_271_(800x600).jpg)


The fan installed on the engine:

(https://i.postimg.cc/qRGcXKYZ/Inline_Twin_272_(800x600).jpg)



Thanks for following along, and stay tuned for more.
Yogi
Title: Re: Freelance Inline Twin
Post by: cnr6400 on March 13, 2019, 09:09:55 PM
Great work on the fan Yogi. Liked the 3D printed tooling! Looks like the engine's almost ready to bark.
Title: Re: Freelance Inline Twin
Post by: Admiral_dk on March 13, 2019, 10:11:48 PM
Nice use of modern tools - CNC + 3D printing => great result  :ThumbsUp:
Title: Re: Freelance Inline Twin
Post by: Ye-Ole Steam Dude on March 13, 2019, 11:24:54 PM
Hello Yogi,

That engine is so beautiful and a neat job on making the fan.

Have a great day,
Thomas
Title: Re: Freelance Inline Twin
Post by: 90LX_Notch on March 13, 2019, 11:30:51 PM
Nice!

-Bob
Title: Re: Freelance Inline Twin
Post by: toolznthings on March 14, 2019, 01:37:06 AM
Genius work !! Looks fantastic  :ThumbsUp:
Title: Re: Freelance Inline Twin
Post by: Art K on March 14, 2019, 01:50:39 AM
Yogi,
The engine looks great, looks like one more reason to get a 3D printer. That fan looks really good.
Art
Title: Re: Freelance Inline Twin
Post by: Zephyrin on March 14, 2019, 08:27:48 AM
Wow, beautiful job with this engine.
I like very much this modern way to build model engine, up to date technical and engineering, immaculate results...
Title: Re: Freelance Inline Twin
Post by: fumopuc on March 17, 2019, 04:58:10 PM
Hi Yogi, I like the fan.
Title: Re: Freelance Inline Twin
Post by: Roger B on March 17, 2019, 05:18:14 PM
Excellent work on the fan  :praise2:  :praise2:
Title: Re: Freelance Inline Twin
Post by: yogi on March 19, 2019, 10:00:26 PM
Thanks everyone for the kind comments! It's very much appreciated.  :cheers:

The 3d printer has been a useful tool. It opens up new possibilities, and it's a lot of fun!


I could use some input from you guys on how I should proceed with the radiator.
My plan is to use a PC cooling radiator. The main reason I would like to go this route, is to safe time. This engine build has been going on for quite some time, and I have a number of other project I would like to get started. And these radiators aren't bad looking either.
I purchased a couple of 140mm and 120mm radiators.
The thing where I'm scratching my head right now, is the plumbing. The PC radiator has the inlet and outlet on the same side of the radiator, and the coolant flows through it in a U shape. One thought I have is to plumb it the way it is with a tube from the top of the engine, where the coolant outlet is, down to the the radiator and through it. The block looking part below the radiator would be a tank to increase the coolant capacity.
Another thought is to modify the radiator, by adding a cap and inlet at the top, and turning it into a more traditional radiator.

I modeled the 140mm radiator in CAD, to see how I could mount it.

(https://i.postimg.cc/Hsds9N9t/Inline_Twin_273_(800x618).jpg)

(https://i.postimg.cc/x1dfWb7J/Inline_Twin_274_(800x618).jpg)

(https://i.postimg.cc/pL7H4cz4/Inline_Twin_275_(800x618).jpg)


The 140mm radiator mocked-up:

(https://i.postimg.cc/KY6mkpYB/Inline_Twin_276_(800x600).jpg)

(https://i.postimg.cc/NjPsYjqN/Inline_Twin_277_(800x600).jpg)

(https://i.postimg.cc/KYkZYhmm/Inline_Twin_278_(800x600).jpg)


As a comparison, the 120mm radiator. I think this one is a bit small for this engine.

(https://i.postimg.cc/d1Gw8R7X/Inline_Twin_279_(800x600).jpg)

(https://i.postimg.cc/5y11pHLt/Inline_Twin_280_(800x600).jpg)

(https://i.postimg.cc/ZKHY7Lfz/Inline_Twin_281_(800x600).jpg)



Any input is greatly appreciated.

Thanks,
Yogi
Title: Re: Freelance Inline Twin
Post by: kuhncw on March 19, 2019, 11:50:27 PM
Hi Yogi,

Those are nice looking radiators.  If you mount it with the inlet/outlet on the bottom, consider venting the top tank to purge any air when filling the system. 

Would laying the radiator on its side in cross flow configuration work?

Chuck

Title: Re: Freelance Inline Twin
Post by: toolznthings on March 20, 2019, 01:29:36 AM
Hi,

George has a modified radiator for his Ford V-8 made from computer radiator. See if he can add some advice.

Brian
Title: Re: Freelance Inline Twin
Post by: Art K on March 20, 2019, 02:00:35 PM
Yogi,
Chuck beat me to the punch, I was going to suggest the cross flow idea. It might make mounting complicated though. One other thing if you mounted the tank higher it would be like the standard expansion tank on a car. You could have the filler cap in the tank and not drill holes in the radiator. That could work without looking to ugly.
Art
Title: Re: Freelance Inline Twin
Post by: gbritnell on March 20, 2019, 02:52:49 PM
When I used one of those radiators on one of my engines I found that there is a baffle in the tank. Where you see that crease in the tank is where the baffle is. Most engines have the cool water going in the bottom of the engine or water pump and as it heats and rises it then goes to the top of the tank. I guess you could force the water through the rad with the way the fittings are but I plugged one and then made another and epoxied it to the narrow tank on the other end. When I drilled in the center of the large tanks is when I found the baffle. I went in with a rotary grinder and cleared out as much as I could for the water flow. Where I drilled the hole is where I installed the filler neck.
Title: Re: Freelance Inline Twin
Post by: kuhncw on March 20, 2019, 04:14:55 PM
Yogi,

George's radiator installation looks pretty slick.

If you don't want to cut into the radiator, perhaps something like the attached sketch would work.  The top tanks are still divided, but both have a way to vent air when filling the system or in case you get any combustion leak into the coolant.  The orificed vent on the piping back to the engine will bypass just a bit of coolant but should not affect cooling much.  Anyway, this might be a way to avoid modifying your radiator.

Chuck
Title: Re: Freelance Inline Twin
Post by: Rustkolector on March 20, 2019, 04:24:06 PM
Yogi,
You have a two pass radiator arranged with two separate cores and a partitioned tank at the coolant connection end. There are two reasonably good ways to apply these radiators to gas engine cooling. The first is as George has mentioned by cutting the partition and adding a new bottom connection.   

The other way requiring only one minor mod to the radiator itself is as Chuck and Art have mentioned, to rotate the radiator 90⁰ and mount it so the radiator coolant connections are on the side for a two pass cross flow cooling system. Your engine coolant discharge would then be plumbed to the top radiator connection. The bottom connection is plumbed to the suction side of the coolant pump. You still need to fabricate and mount a relatively small cylindrical expansion tank vertically on the coolant connection at the side of the radiator. This provides coolant fill port, expansion space, and proper venting. Tee a bottom drain of the expansion tank into the coolant suction line to the pump. You also need a small vent tube from the top most part of the top radiator core top tank into the side of the expansion tank near its top. This vents any entrapped air in the coolant to the expansion tank and it aids filling the system. The top of the expansion tank should be the highest point in the system and should be vented to the atmosphere. Filling the cooling system with a gear pump takes a little time or a drill motor to spin the engine, but it should purge the air out of the cooling system as you pour the coolant into the expansion tank. 

These little radiators have impressive cooling performance even with low flow electric computer fans. They are very efficient at their job. They were designed to cool with 10-15 degree F temperature differentials between coolant and ambient air temps. You will have a minimum 70-80 degree F temp differential to work with. The 120mm radiator is likely more than adequate. For example, I use a 120mm radiator on a 1Ē bore 4 cylinder gas engine model generator at 24 watts electrical load continuously for hours @ 70 degree F ambient with a 5 speed 120mm electric fan set on low/medium speed.   

Also note, since your engine is aluminum and your radiator is probably brass, there is a high probability that galvanic corrosion could take place between these two metals if an electrolyte is present (coolant). Either drain your coolant after use or pick a glycol based coolant with an inhibitor specifically for this condition. 

Jeff
Title: Re: Freelance Inline Twin
Post by: yogi on March 21, 2019, 12:50:18 PM
Thank you gentlemen for the input and great ideas! It's very much appreciated.  :ThumbsUp: :ThumbsUp: :ThumbsUp:

Yogi



Title: Re: Freelance Inline Twin
Post by: Roger B on March 29, 2019, 04:58:50 PM
I have a similar radiator as was planning to go crossflow with a T piece on the top connection to act as a filler/vent.
Title: Re: Freelance Inline Twin
Post by: yogi on April 03, 2019, 11:22:12 PM
Thanks for the input Roger. Using the radiator cross flow would be the easiest, I'm just now sure if I'm going to like the look of it. George's method is my favorite right now, even though I haven't decided which way i'm going to go yet. I'm giving myself some more time to think about it. Typically sitting in the shop staring at it for any length of time...
  :thinking:  :wine1: :zap: :DrinkPint: :thinking:  :Lol:
Title: Re: Freelance Inline Twin
Post by: Admiral_dk on April 04, 2019, 11:30:05 AM
Quote
I'm giving myself some more time to think about it. Typically sitting in the shop staring at it for any length of time...

Now here is something I really can relate to  ;)  I used to work much faster when I was young => many errors => slowing down, reduced the errors dramatically => slowing further => hardly any errors or anything done or at least for my own benefit  ::)

So I should probably go back to making more errors  ;)  that is if I could find the time - still nine years to retirement.

I'm sure that you will come up with a solution that will satisfy you - even if it is the second version  :cheers: