Lil' Henry Build

[Generatorgus]

I'm not at all sure why I started building this engine.


Machine work on my Wyvern project is complete and all I have remaining to do is reassemble it and spin the flywheel. If the new carb works it would pretty much complete the project.
And then the doubt thing starts to gear up. What if the carb doesn't work, now what, what if this, what if that? Not an earth shaking dilemma, but I tend to obsess a bit. So I decided to do something else.


Winter is creeping in and I was just getting around to putting summers things away. I decided to run my engines one more time before they went on the shelf.
I had the half scale H. Ford running and my thoughts ran to building a new version, modified somewhat from the original design. Next thing I'm digging around and gathering parts for it.


While rummaging pipe fittings I came on a nice older style 3/8” brass tee. Half scale would warrant a 1/2” tee, but I put it with the other parts anyway. After gathering everything I had on hand I started thinking on what other material I might need and went back through the small box I gathered and re-found the 3/8” tee. What if I try making the engine in a smaller scale?
With pencil and paper in hand I started rough plans for a 1/3 scale version of the engine and now I was off on a new adventure.


As is usually my methodology, after some figuring, I'll make a part and if it looks right I'll then figure out what I need for next part. I never have a complete plan, dimensions and such, just build as you go.
What I had in front of me was the tee fitting, so it went in the mill vise, if it works out I'll try to figure out what to do for the base.


For a casting this fitting was very square, so I chose to hold it with the leg of the tee up.
The rim and bore were machined using a boring tool, then the fitting turned up and the
procedure repeated. The bore was made to fit a piece of steel aircraft tubing that I deemed would be in the range I needed for the cylinder, although I would have to order it.
I used aircraft tubing on the half scale and it worked out good.





That went well so my attention turned to the next logical part, the base for the tee. The original and my half scale use pipe flanges, but I had nothing on hand and didn't feel like spending any money yet(plenty of opportunities to do that), so I would have to conjure something up.
More rummaging and my attention fell to a partially disassembled 1 1/2”brass globe valve that I bought for about scrap price, just to get the really nice looking hand wheel, thinking I might use it as a flywheel for a model engine.




I already used the stem as bar stock and the disk was still laying inside (I had to search globe valve terminology to come up with disc). It had most of the features I would need for the flange, so a put it in the lathe chuck and started carving to see if the flange was really there.



After a few minutes of carving [FONT=SimHei, monospace]I[/FONT] decided it would nicely.







Next in my way of thinking I needed a temporary base to mount the engine and I came up with a piece of yellow pine gleaned from an ancient panel door.
I tend to save wood from things I think may have some use sooner or later, but most eventually get chopped up for kindling. This piece was already in that pile.



I also dug out the hand wheel from the donor valve to see if it was anywhere near right for the flywheel and it looked pretty good visually, but whether or not I could use it is still a question.






I've used hand wheels (valve handles) for some of my electric models before I had any machine tools and they worked, but they always wobbled. There were also questions as to the weight and circumference to answer, so this would be the next to try to figure out.


Flywheel: full scale recommended 12-14 dia ,10-14#
“ “ my ½ scale (hand wheel) 7” dia, 2 lb -6oz
“ “ 1/3 scale (hand wheel) 4 5/8” dia 7.6 oz.


More than likely too small, but I'll try it because I like it. I can always find another project to use it on.
I originally thought the hand wheel I used on the half scale might be too light. It actual had grip knobs cast into the rim, I thought they looked neat, but after getting bruised several times and then had the running engine go to launch mode when it worked it's way off of the bench, I cut the knobs off and re-machined the rim. The substantial loss of weight didn't seem to make much difference.
In the early stages of that build I had both of the knobbed hand wheels mounted side by side, in an effort to get the weight up.




After machining these simple parts, the build is on.

GUS

 

[huntandfish]

A question about your Wyvern.
I am currently building a Wyvern but I am struggling to undersatand how the cam shaft mount fits under the carank so the gears engage . I think I have machined the bits as per the drawings but it doesnt align. Any chance of a photo of yours with the flywheel off?

 

[Generatorgus]

A question about your Wyvern.
I am currently building a Wyvern but I am struggling to undersatand how the cam shaft mount fits under the carank so the gears engage . I think I have machined the bits as per the drawings but it doesnt align. Any chance of a photo of yours with the flywheel off?

This was my solution. I was able to salvage the bracket, but had to mill clearance on the base. I've seen other ways, too.



The skew gears you use may have be a different size which will effect how you have to modify the bracket.
If my solution will work for you, I would suggest a flathead screw at least on the hole behind the gear. Just not much room there.

If I remember correctly, I had to modify the front end bracket and the rocker arms also.
You can PM me if you have any other questions.

GUS

 

[Generatorgus]

Continuing work on the cylinder assembly.​

Although I intended to use steel aircraft tubing for the cylinder, I was happy to find I had a large enough piece of durabar left from another project.

The outside diameter turned to fit the brass tee, and then bored and honed to the chosen .406” I decided on, based mostly on the ID of the tubing I was going to use.
Also an alum breech plug made, to extend to just about the holes that will be drilled and tapped for the spark plug and valve fittings at the center of the tee. Fitted with an appropriate size o-ring, it will be held in place by a set screw in the rim of the fitting.​

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While up front I made a 10-40 thread spark plug, switching from the usual Teflon core to Corian left over from my kitchen counter top.
Shown here with a 5/16-32 I previously made.
I'm a bit surprised with the how much the closeups pics are showing me minor flaws and roughness.
The picture quality on macro setting is much better than I was getting with my old camera.​

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I also made an extension/cradle added on the flange. This was added to close the gap that would have been at the junction of the cylinder and valve fitting holes inside the tee, also it helped to get the cylinder up to match the center line of the engine.​

It was an after thought. On my half scale I filled this space with JB weld. If I was inclined to make a do-over I would have plugged the space before boring for the cylinder.
Incidentally the entire assy. is Loctited.
The mounting holes were also drilled.​

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The piston and connecting rod were also made and given a quick leak down test, which was satisfactory.​

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A few pics of the conn rod construction.
Pieces of brass rod drilled just enough to accept the 3/16” drill rod and silver soldered.
The rods were left long and cut off after soldering, only to facilitate holding them in place while soldering.
Then milled, drilled and reamed for the wrist and crank pins.​

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The alignment of the conn rod ends when soldering is fairly critical and I didn't right on my first try and required a do-over.​

Next for the front of the engine would be the valving, which I haven't made any final plans for yet.
The original H. Ford uses an oiler for a fuel tank and a flapper type check valve for the intake valve. When I built the half scale I used a check valve (both types,ball and flapper) and they didn't work very well, and in the end used valve cages inside of brass1/8” pipe els.​

I'm hatching a plan to use a 1/4” MPT tee made to look like a check valve, but have a valve cage mounted thru the underside, but in the meantime I'll start making the back end of while I try to figure out the details for the valves​

 

[cfellows]

Hey, Gus, this all looks kind of familiar! I can tell you why you're building it... it will be one of your favorite engines when you're done!

The version I built has a 13/16" bore and I think I used a 3/4" pipe tee. Mine also has a 7 1/4" Don't know how close you are following the original plans. I departed a lot from the original plans.

I just designed a new carburetor which I tried out on it and it works good.

Are you planning to follow the original plans pretty closel?

Chuck

 

[Generatorgus]

Hi Chuck, I followed your build with great interest, and I liked the ways you departed from the original plan.
I never had plans for the half scale I built, although I tried to stay with the original from what pictures I could find to scale it down. But in the end I had to change the valves and fuel supply in order to make it run right.
That engine was my first and it is my favorite and probably will hold that position. I learned a lot from building it.

My intent is to make this one at least look similar to the original full scale version, but I can't stay with it 100 percent. They are a simple engine with surprising complexities. And yes it will probably be my favorite if I can make it into a good runner.

You build some very interesting stuff and I follow along as it comes, please keep it coming.

 

[vcutajar]

Following along Gus.

Vince

 

[Generatorgus]

The back end of the engine is a simple U shape two side plates and a bottom plate joined by cap screws. So simple I forgot to take pictures. This is the earliest I took. I already had the holes for the crankshaft bushings and the location for the cam bushing spotted,and checking to make sure I had enough room on the base board.​

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Picking the cam gears was easy. Last summer an old friend gifted me some stuff from his shop that he thought would be useful in my model making. Durn right useful, part of it was this little box of treasures. Just the right size for models and there's more than one set of 2:1 ratios in that box, as well as some bevel gears.
I made use of the pair on he left, the 15 and 30 tooth, perfect.
All I had to do was make some arbors.​

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For the flywheel, I really wanted to use that hand wheel and I was more intent on that, the gears could wait a bit.
Since of had previous problems with chilled castings I sampled the hub with a file, yeah, right, hard as a brick.
Some times you just can't anneal the hardness out of things , but I hopefully stoked up my already burning wood stove and got it real hot then dropped the wheel in the inferno and put more wood on top. In about ten minutes I enjoyed this pleasing sight.​

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I left it where it was and put more wood on and didn't disturb it until the next morning.
I went right to it, even before my breakfast.​

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I dusted the fire scale off and file tested the same spot, wonderful, soft, machinable iron.
I wanted to hold it by the inside of the rim to machine it, but the chuck jaws wouldn't fit between the spokes so it ended up in the 4 jaw, centered up best as possible and cleaned up one side of the hub so I could get a good grip on it, then back to the three jaw.
In order to true the rim I would have to cut it, but how to keep it round.
I thought about using a radius milling cutter or even grinding a lathe bit. But I had visions of it flying out of the chuck as they would cause too much friction.
I ended up making a series of light angle cuts with the cross slide set at different angles and blending with a file.
It runs true and still has that nice round rim. ​

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To eliminate the square center hole I bored it with an end mill and glued an insert which was bored and a keyway added. Came out looking pretty good. Now I can only to hope it will work.​

Crank shaft were components all machined.​

Bushings and timing gears added, and all assembled for trial fit up.​

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And everything turning smoothly.​

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I now have to move on and figure out what I want to do with the valves.

GUS

 

[Philjoe5]

That flywheel is looking good Gus. I like how you take something laying around and turning it into something that seems perfectly at home on a model engine.

I'm also thinking about the coolant container on your Wyvern

Cheers,
Phkil

 

[oneKone]

Awesome work gus. These engines are just so cool! Your doing a bloody impressive job, I'm looking forward at following this build.

 

[idahoan]

Hi Gus

Enjoying your build here and as always your knack for digging through the scrap box and coming up with a gem!

Dave

 

[Generatorgus]

Guys, thanks for the comments and kind words.
I'm not a very accomplished machinist and it's a very steep learning curve for this aging carpenter.
One thing I've always been fairly good at is reusing salvaged materials, it's in my blood, I can't help it. My wife calls me cheap, I say I'm frugal.;D
GUS

 

[Generatorgus]

For the exhaust valve the original full scale engine used a globe valve converted to use a regular type valve, except that the valve stem extended thru the head of the valve with the spring on top.
I tried and came up with nothing but failures, couldn't get them to seal, and finally (after shelving the project for more than a year) resorted to a valve cage. I can only blame my inexperience at the time for those failures.
I've since gotten a little better at valves, and I favor valve cages, they work well for me. I'm going to try try to incorporate a valve cage in a tee and try to make it look at least similar to the original.​

Although the engine, at this point, was running but the oiler fuel tank, with it's drip supply, it had to be in flight refueled, as the little oiler didn't last more than a minute or so and it still didn't run well.

Much later I basically redid the entire cyl. assy. with valve cages, a normal fuel mixer, dumped the oiler and added a fuel tank. Runs fine now, but a fair step away from the original design.
This rendition will have a faux oiler with a mixer incorporated somewhere, but I haven't gotten to figuring out the details yet.

After spending some time at my makeshift drawing board, I came up with something that should work and still look more original.
The intake valve in a ¼” MPT tee should be fairly simple, complicated only by how well I'll be able to handle the small (for me at least) size.
This will be a loctited assembly​

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The exhaust has more complications, and I don't think it's a good idea to put the spring on top, but I'll give it a try. It worked for Henry, but for how long?​

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I'll start on the easier intake valve.​

After making a fixture to hold the fitting castings, using my milling machine. I started by drilling a 1/4” hole all the way thru the leg of the inverted tee then the leg tapped ¼ -40 straight thread​

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Next the valve cage was turned, valve stem hole drilled and reamed 3/32”, the chamber milled in and the port drilled. ​

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The intake valve turned and light spring salvaged from an old battery drill test fitted. Shown here with the valve cage being test fit.​

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I made a George Britnell type valve seat cutter and, of course, cut the seat in the cage valve and finished up by lapping the valve in with lapping compound.
Inserted in the end of a length of plastic tube and submerged in water, the valve past my initial lung powered blow test. Real proof will be tested when I try it in the engine.​

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Back at the mill, the fitting casting still in the fixture was rotated in in the mill vise and the holes drilled and milled flat at the bottom to a depth I figured would work for the MTP thread and the intake and exhaust ports milled.​

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At about that point I discovered the my plan to tap 1/4” MPT for the close nipples wasn't going to work there was not enough room for the depth the tap needed. I didn't want to start grinding at my new $40 tap to see if it would work as a bottoming tap, and I never saw a bottoming pipe taper tap.​

Back at the drawing board I determined the a stub nipple (threaded on one end only), loctited in place should work.​

Stub nipples were made and the assembly loctited in place.

Fitted with a threaded cap hex cap and an el made for the faux oiler, another part of this engine complete.​

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The faux oiler/mixer will be next, as I'm hesitating on the design of the exhaust valve.​

GUS​

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[Heffalump]

I love this! I like the way you're using these fittings, this is inspirational stuff!

 

[cfellows]

Very original, Gus. I was wondering where you were going to find tee fittings like those used in the original engine. Never occurred to me to use model pipe fittings.

Chuck

 

[Rivergypsy]

Looking very good, Gus - I like it

 

[Philjoe5]

Looks good Gus. I may try one of these engines next. I'm following along

Cheers,
Phil

 

[motoseeya]

If you need a bottom tap for pipe use a elec. tap it cuts even all the way so you can make a bottom tap if you need it. pipe taps cuts on a taper .Thm:

 

[Generatorgus]

Guys, Thanks for the comments.

Chuck, I was thinking about using a check valve from PM research for the exhaust, and just by coincidence, found that Vascon used one for his current build of the 1/2 scale build of the Ford Quadricycle enginine.
But my fingers couldn't reach that far into my pocket.

Motoseeya, I didn't think of that.

GUS

 

[idahoan]

Nice work on the valve assembly Gus.

Dave