Model Engine Maker

Engines => Your Own Design => Topic started by: Brian Rupnow on July 06, 2021, 11:25:01 PM

Title: T head engine by Brian
Post by: Brian Rupnow on July 06, 2021, 11:25:01 PM
Today seen the beginning of a new engine.---The design phase, at least. After recently seeing  an Upshur T head coming together on  HMEM and a post by Vederstein about  building a T head engine I thought that would be an interesting engine to design and build. I'm in no rush to start building, but I know how that generally works. I spent most of today bringing the design along to this stage, and will probably finish up the cylinder head tomorrow.
(https://imagizer.imageshack.com/img922/9986/wfAAIi.jpg)
(https://imagizer.imageshack.com/img923/4479/YvNtoy.jpg)
Title: Re: T head engine by Brian
Post by: crueby on July 06, 2021, 11:38:23 PM
Very interesting look to that engine, will be watching along!
Title: Re: T head engine by Brian
Post by: Brian Rupnow on July 07, 2021, 05:53:45 PM
Great progress made this morning. I decided to keep the engine air cooled. I think the grooves in the cylinder and cylinder head look good.
(https://imagizer.imageshack.com/img922/8675/XqkVkd.jpg)
Title: Re: T head engine by Brian
Post by: mikehinz on July 07, 2021, 07:58:07 PM
Brian, I like the look of this engine so far!  I'll be closely following your progress in the design and then during building.

More great work!

Mike
Title: Re: T head engine by Brian
Post by: Brian Rupnow on July 07, 2021, 09:23:37 PM
Okay---We've got a carburetor, carb adapter, heavier crankshaft and an exhaust system. Also a set of tappet guides and two very long valves, riding in valve cages. Tomorrow I will stick a set of points and an ignition cam on it, and probably a gas tank.
(https://imagizer.imageshack.com/img924/856/beEUsr.jpg)
Title: Re: T head engine by Brian
Post by: crueby on July 07, 2021, 10:04:57 PM
Very interesting looking design - are the valves themselves at the top of the rods coming off the eccentrics, out on the 'arms' of the tee? Or is there a rocker inside?
 :popcorn: :popcorn: :popcorn:
Title: Re: T head engine by Brian
Post by: Brian Rupnow on July 08, 2021, 03:07:49 PM
The Tee Head engine design is finished. Fortunately, I was able to sneak the ignition points and condenser in behind one flywheel (which is hidden in this model), without offsetting the flywheel any. I also added a gas tank and a pleasant looking mounting bracket. None of the detail drawings are made yet, but the design is finished, so detail drawings are pretty simple now.
(https://imagizer.imageshack.com/img923/114/RgxUR5.jpg)
Title: Re: T head engine by Brian
Post by: Brian Rupnow on July 08, 2021, 03:38:02 PM
Chris---This kinda/sort answers your question. The cams which operate the valves are on the large gear, which is driven at 1/2 the crankshaft speed.  Adjustable height tappets  bear on the cams, and these tappets run inside a guiding sleeve. The end of the valve stems ride on top of the tappets. The head of the valves are in the combustion chamber. The valves are "direct acting" with no rocker arms. It is called a t head because the combustion chamber is shaped like a capitol T with the cylinder being the upright and the two valves are in the arms of the T.
(https://imagizer.imageshack.com/img924/1391/fa0OAH.jpg)
Title: Re: T head engine by Brian
Post by: crueby on July 08, 2021, 03:45:10 PM
Great diagram/explanation - thanks!!!
Title: Re: T head engine by Brian
Post by: Twizseven on July 08, 2021, 03:59:27 PM
Brian,

Like the look of this one.  One thing puzzles me.  I cannot see any valve springs.  I appreciate that as the cam rotates and the follower goes with it, the valve will drop and thus close, but I cannot see this being quick enough or positive enough.  When I first saw your design I had wondered whether you had hidden them in the long valve guide.  Or another possibility have them between the top of the valve guide and maybe a washer and splitpin/collet on the valve.

Regards,

Colin
Title: Re: T head engine by Brian
Post by: Brian Rupnow on July 08, 2021, 10:45:01 PM
Colin---it's a trick. You don't see them because I haven't modelled them yet. I'll get to that tomorrow. I haven't designed any way to get oil into that enclosed crank-case yet either.
Title: Re: T head engine by Brian
Post by: Brian Rupnow on July 09, 2021, 12:19:34 AM
Colin--I added some valve springs for you.---Brian
(https://imagizer.imageshack.com/img922/4231/DqAl3S.jpg)
Title: Re: T head engine by Brian
Post by: Twizseven on July 09, 2021, 09:40:27 AM
Brian,

That looks better  :) :) :) :)

Love your coloured CAD renditions.

Colin
Title: Re: T head engine by Brian
Post by: Brian Rupnow on July 09, 2021, 01:50:40 PM
Now we have an oil filler tube for the wet sump, a drain, and some totally awesome gear guards. Other than keeping your fingers out of the gears, these gear guards cut down a lot of the noise from the gears meshing.
(https://imagizer.imageshack.com/img922/388/89Hpif.jpg)
Title: Re: T head engine by Brian
Post by: bent on July 09, 2021, 04:13:00 PM
Looks good Brian.  Could you put an oil sump/splash shields on the gear guards as well, or are you planning to just run dry gears?
Title: Re: T head engine by Brian
Post by: Brian Rupnow on July 12, 2021, 02:04:51 AM
I just coat the gears in good bearing grease. I was getting bored. Oh Oh--I'm having machining withdrawal. I haven't built anything since I made a set of rings that worked. I went and seen my favorite material guy and paid $25 for a piece of 6" x 1" x 12" long piece of aluminum.  A couple of days drilling, tapping, counterboring, sawing, and milling work has yielded the main frame of my t-head engine. I have a visiting grandson from out of town, so might not machine anything more for a few days. Damn, I like a day spent in my shop!!!
(https://imagizer.imageshack.com/img924/7726/J52gU6.jpg)
Title: Re: T head engine by Brian
Post by: Brian Rupnow on July 12, 2021, 10:58:39 PM
I hate chain drilling!!! The original plan was to bolt this part to the faceplate and bore it out to the required size. Sadly, my lathe which is supposed to swing 12" really only swings about 11 1/2" so, it has been chain drilled instead. Now to knock the piece out and smooth up the resulting mess. I hope that I can tie this part to my rotary table to clean everything up.
(https://imagizer.imageshack.com/img923/7764/X67dwX.jpg)
Title: Re: T head engine by Brian
Post by: Brian Rupnow on July 12, 2021, 11:24:45 PM
I would have had to build some more fixturing to mount this on my rotary table. This is where my oscillating drum sander really pays for itself. The curved area is non critical, just a visual thing, and this took about five minutes on the oscillating drum sander.
(https://imagizer.imageshack.com/img923/4814/RGAoPs.jpg)
Title: Re: T head engine by Brian
Post by: Brian Rupnow on July 13, 2021, 01:36:14 AM
(https://imagizer.imageshack.com/img922/1663/fFK2IS.jpg)
Title: Re: T head engine by Brian
Post by: Brian Rupnow on July 13, 2021, 03:48:30 PM
Well, so far, so good. The cylinder base mounts to the main chassis. Depending on what my wife has planned for me today, I might even get a cylinder up there.
(https://imagizer.imageshack.com/img924/6715/uHlvNO.jpg)
Title: Re: T head engine by Brian
Post by: crueby on July 13, 2021, 03:50:39 PM
Incredible progress! Very nice shape to the engine.

 :popcorn: :popcorn: :popcorn:
Title: Re: T head engine by Brian
Post by: Brian Rupnow on July 13, 2021, 08:04:58 PM
We have a cylinder. It is pretty, it fits where it's supposed to, and after honing the bore with a 3 stone brake hone it measures about 1.001" bore. That's all for today folks. I will get some mounting holes drilled in the cylinder tomorrow.---Brian
(https://imagizer.imageshack.com/img923/7060/TCnKb9.jpg)
Title: Re: T head engine by Brian
Post by: mikehinz on July 13, 2021, 08:29:20 PM
Brian, I have a question on your build.  One of you drawings shows what looks like a Traxxas carb.  Is that what you're going to use on this engine?  I know from some of your other parts, you've used at least 3 different carbs, 1) the cfellows carb 2) the JAG carb 3) the gbritnell carb.  Which carb are you going to use and which one do you think works best and that you like the best?  As a bonus question, do you ever use an adapter that acts as an insulator between the carb and the head?

I'm enjoying your build and am watching it closely!

Mike
Title: Re: T head engine by Brian
Post by: Brian Rupnow on July 13, 2021, 10:10:39 PM
The Traxxas carb is my "go to" carb for a fast build. They are ideal for this size of engine. I have made the George Britnell carb, the Malcolm Stride carb, the Chuck Fellows carb, and my modified version of the Chuck Fellows carb. All of these carburetors work well. The carburetors I built were just exercises in "seeing if I could build a carburetor".  And no, I don't use any kind of insulator between the cylinder and the carburetor.
Title: Re: T head engine by Brian
Post by: Brian Rupnow on July 14, 2021, 04:11:18 PM
Due to the way this engine is constructed, the swing of the con rod would hit the side of the cylinder bore on it's way to bottom dead center. This cavity in the bottom of the piston aligns with the cavity in the bottom plate which bolts to it, to give clearance for the swing of the connecting rod.
(https://imagizer.imageshack.com/img922/420/OLIUjZ.jpg)
Title: Re: T head engine by Brian
Post by: Brian Rupnow on July 15, 2021, 01:47:27 AM
And---The miserable piggy of the day award goes out to this cylinder head. It is finished except for the cutting of the cooling fins, but I've managed to put in an entire day on this part. Some days you eat the bear----Some days the bear eats you!!! The bear eat me today on this part, but I'm pleased with it.
(https://imagizer.imageshack.com/img922/6267/A5LJ3M.jpg)
Title: Re: T head engine by Brian
Post by: Brian Rupnow on July 15, 2021, 11:16:01 PM
Today I built the cylinder head for my engine. I still have to put the slots in the cylinder head and plate right below it to make cooling fins.  The only aluminum part left to build now is the gas tank mount. So, I basically have a whole engine here in six parts. Tomorrow I hope to cut the cooling fins and make the gas tank mount, then it will be on to mechanical things.
(https://imagizer.imageshack.com/img923/4965/Om7cWG.jpg)
(https://imagizer.imageshack.com/img922/7739/dWPP54.jpg)
Title: Re: T head engine by Brian
Post by: Brian Rupnow on July 16, 2021, 04:03:21 PM
We now have "fins" in the cylinder heads. They were cut in using a 0.094" slitting saw. I have to go now and introduce myself to Mr. Lawnmower and Mrs. Whippersnipper. My yard is starting to get a bit jungly with all the rain we've been having.
(https://imagizer.imageshack.com/img922/8644/rniUdF.jpg)
Title: Re: T head engine by Brian
Post by: Admiral_dk on July 16, 2021, 09:10:18 PM
Nice progress Brian  :ThumbsUp:

Quote
My yard is starting to get a bit jungly with all the rain we've been having.

Much to be prefered compared to the rain that has partly removed many towns from the map in Germany the other day - 130 found dead so far  :'(
Title: Re: T head engine by Brian
Post by: Brian Rupnow on July 16, 2021, 11:06:44 PM
Admiral---we had a tornado here yesterday. Fortunately it was on the far side of the city from where I live.  Today I went to see my nut and bolt guys, and replenished some shcs that I was getting low on. Also bought the two shoulder bolts that will support the cam gears. Found time to make a gas tank mount. Now all of the aluminum parts of the engine main body are finished. Tomorrow I may dive into the mechanical parts.---Brian
(https://imagizer.imageshack.com/img922/5030/Iam4f1.jpg)
Title: Re: T head engine by Brian
Post by: Brian Rupnow on July 17, 2021, 05:57:22 PM
Here I am, waling away on a piece of 2 1/2" diameter hot rolled to make the 50 tooth gears from. The o.d. of those gears is 2.166" x 1/4" thick plus 7/8" diameter hub on one side.
(https://imagizer.imageshack.com/img923/5918/j0TycV.jpg)
Title: Re: T head engine by Brian
Post by: Brian Rupnow on July 18, 2021, 08:59:54 PM
Got up nice and early this morning and cut both 50 tooth gears. Everything worked out nice, no extra teeth. Maybe I'll do the 25 teeth gears tomorrow. It has been a lovely day here, had a family birthday party for my daughter and I  out in my backyard. There are twelve of us now in the family. I'm the oldest at 75, Davy's the youngest at 1 1/2 years.
(https://imagizer.imageshack.com/img922/9399/htMn2t.jpg)
Title: Re: T head engine by Brian
Post by: Brian Rupnow on July 19, 2021, 01:26:56 AM
Holy Gas Tank, Batman---Were going to try something a little different. I've made about two dozen gas tanks. Many had the end plates silver soldered in place. A roll of silver solder costs about $100 here.  Then I found out that I can J.B. Weld the endplates in and they never leak, but you have to be aware of your construction procedure and have any other soldering or welding finished before you use the J.B. Weld. Tomorrow, I am going to Tig weld the endplates into this tank. Of course there will be a bit of prep work first, probably a counterbore in each end of the pipe, and endplates made with a decent chamfer for the weld to fill. I'll let you know how that turns out.
(https://imagizer.imageshack.com/img924/4706/NZ4Yju.jpg)
Title: Re: T head engine by Brian
Post by: Brian Rupnow on July 19, 2021, 04:43:46 PM
Damn, I just lost an entire post.---Here we go again. The tig welding turned out very nice. No, it's not the perfectly overlapping "fish scale" pattern that a professional welder would lay down, but it works for me. A bit of clean-up on the lathe and it should be a beautiful thing. I simply can not afford the $$$ for brass, so I will be painting the gas tank and the flywheels in some complimentary colour.
(https://imagizer.imageshack.com/img923/1899/isiWz5.jpg)
(https://imagizer.imageshack.com/img924/1313/Kg99Hz.jpg)
Title: Re: T head engine by Brian
Post by: Brian Rupnow on July 19, 2021, 05:35:56 PM
And it's a lovely thing, what a bit of lathe and file work will do to finish off a welded gas tank.
(https://imagizer.imageshack.com/img924/889/46eWfU.jpg)
Title: Re: T head engine by Brian
Post by: bent on July 19, 2021, 06:09:20 PM
My Tig skills are about on a par with yours, Brian.  And I agree, it's amazing what a little bit of filing and machining does to smooth up the welds.
Title: Re: T head engine by Brian
Post by: Brian Rupnow on July 20, 2021, 04:06:52 PM
The outer diameter of the crankshaft bearings have been coated with J.B. Weld and located in their bores. Before it has had any chance to set-up, a 1/2" diameter cold rolled shaft has been ran thru both bearings, and the two halves of the crankcase have been reassembled with locating pins and bolts. The two 25 tooth gears were finished this morning and then slid over the ends of the shaft to make sure that they mounted and meshed properly with the camshaft gears.---They do!!!
(https://imagizer.imageshack.com/img923/9817/GOElvj.jpg)
Title: Re: T head engine by Brian
Post by: Brian Rupnow on July 21, 2021, 11:12:13 PM
Things are going to slow down for a little while. One of my old customers has come foreword with a request for some new welding fixtures for one of the big three automotive companies. It's design only stuff. Fabrication will be done elsewhere. I'm not sure just how much work there will be, but probably not much.---It would be nice if there was a couple of weeks work---that would buy me a new metal cutting bandsaw. My current bandsaw is an old woodcutting saw that I modified to cut metal. It works, but it is painfully slow.
Title: Re: T head engine by Brian
Post by: Brian Rupnow on July 22, 2021, 08:54:50 PM
The welding fixture is completely designed and sent to my customer, who has to go to his customer for "design review". After that has happened I will complete it and make detail drawings.---Now--Back to my own stuff. I finished the welding fixture design about noon today, and spent the rest of the day machining valve cages. In a perfect world, they would be a press fit into the head. In the real world, you can't press them too hard because they are made of brass. So, they are coated with #638 Loctite and lightly pressed into place with my shop vice. After they set up for 24 hours or more I will drill the intake and exhaust port thru the cylinder head and the valve cages at the same time. I have not used my special valve guide cutting tool yet to prepare the seats to mate with the valves. That is just about the only thing left to do to the valve cages. I will make the valves later today or perhaps tomorrow. I did stop by my metal suppliers today and picked up a foot of 1 1/2" diameter "stress-proof steel to machine a one piece crankshaft from.
(https://imagizer.imageshack.com/img922/9105/vTWr7R.jpg)
Title: Re: T head engine by Brian
Post by: Brian Rupnow on July 23, 2021, 07:45:23 PM
Todays nifty trick was to machine a pair of tappet guides. They set between the 50 tooth gears and the sides of the engine frame. They have a 7/8" clearance hole on center to clear the cams, and there will be a 5/16" i.d. sintered bronze bushing pressed into the hole in the top of them to guide the tappets which ride on the cam. The cam is attached to the side of the 50 tooth gear.
(https://imagizer.imageshack.com/img922/921/jLm41Q.jpg)
Title: Re: T head engine by Brian
Post by: Brian Rupnow on July 24, 2021, 09:30:46 PM
I had to take my chainsaw over to my oldest son's place and play "Johnny Lumberjack" this morning and take out a couple of big trees for him. This left me with a bad case of "lazyitis" this afternoon, so I made two parts for my engine that didn't require a lot of thought. The brass part is the adapter for the Traxxas carburetor, the aluminum piece is the exhaust.
(https://imagizer.imageshack.com/img922/8296/VsKJXj.jpg)
Title: Re: T head engine by Brian
Post by: Brian Rupnow on July 24, 2021, 10:35:38 PM
Ah Heck---I couldn't wait to see how they looked on the engine, so I tapped the cylinder head and installed them!!!
(https://imagizer.imageshack.com/img924/4513/rDJEdH.jpg)
Title: Re: T head engine by Brian
Post by: Brian Rupnow on July 25, 2021, 03:10:40 PM
I ran into something a bit strange yesterday. When I threaded the ends of the exhaust and carb adapter for the engine yesterday, the parts were held in the lathe chuck and the die was held in a collet in the tailstock chuck. No problems were encountered, I even ran a standard 3/8"-16 nut up the thread to ensure that everything was Kosher. When the cylinder head was tapped 3/8"-16 it was held in the milling machine vice and threaded by hand with a tap and standard handle. After screwing things together yesterday afternoon, they were crooked!! It doesn't show in the picture I posted, but they were quite visually crooked. I didn't want the Loctite to set up, so I disassembled things. This morning I held the cylinder head in my mill vice and a tap in the milling machine spindle and turned the spindle by hand, and the tap was cutting metal. I ran the tap in until it bottomed out, removed it, and cleaned up the ends of the cylinder head. I then held the inlet (carb adapter) in the chuck of the milling machine, applied a bit more Loctite and turned the spindle until the shoulders on both pieces were touching each other. I must have had the tap turned at an angle when I first threaded these parts. I would stand and deny that I would make such a dumb mistake, but I can't figure out what else it could have been.
Title: Re: T head engine by Brian
Post by: crueby on July 25, 2021, 04:10:11 PM
Blame it on the shop elves. Usually works for me.....
Title: Re: T head engine by Brian
Post by: Brian Rupnow on July 25, 2021, 06:29:32 PM
It hasn't been a horrible morning, but it sure as heck hasn't been productive. I have one valve to show for it. Beside the valve sets a piece with a 0.1875" hole reamed thru it to check the valve stem for when it is exactly the right size. I can't even begin to tell you why it took so long, but suffice it to say, I've never sanded on anything in my life as much as that valve stem to bring it down to size. I did use a live center in the tailstock to keep the outboard end from flexing while the valve was machined. Maybe tomorrow I'll get lucky and make another valve.
(https://imagizer.imageshack.com/img924/9696/JuSsZt.jpg)
Title: Re: T head engine by Brian
Post by: Brian Rupnow on July 26, 2021, 12:47:12 AM
And as the sun sets into the golden west, two valves are finished. The second valve went quicker than the first, but with that extra long stem both valves required more attention than I have ever given to a valve before.
(https://imagizer.imageshack.com/img924/4453/ZCRIQG.jpg)
Title: Re: T head engine by Brian
Post by: Brian Rupnow on July 26, 2021, 09:34:27 PM
Today, the crooked carb adapter and exhaust have been straightened. I hunted around in my box of assorted springs, and come up with two likely candidates for valve springs. I made two brass stepped bushings which fit over the end of the valves (which are shown in place with "handles" still in place) and retain the valve springs when they are compressed. I still have to cross-drill the ends of the valves for 1 mm pins that hold the spring retainers in place. Not a whole lot to show for a days work, but then I didn't work on the engine most of the day. It was a beautiful 88 degree sunny day here today, and I didn't feel like doing much!!
(https://imagizer.imageshack.com/img923/3040/DVlkpE.jpg)
Title: Re: T head engine by Brian
Post by: Kim on July 27, 2021, 05:45:39 AM
It was a beautiful 88 degree sunny day here today, and I didn't feel like doing much!!

That's funny... when it's 88 here, it's stinkin' hot!  And I also don't feel like doing much!  :Lol:

Enjoying following along with your T-head build, Brian  :popcorn: :popcorn:

Kim
Title: Re: T head engine by Brian
Post by: Brian Rupnow on July 28, 2021, 12:23:35 AM
Kim--the last two years my arthritis is so bad during fall and winter that I dearly love this hot weather. I wouldn't want to have to do any work in it, but my old bones don't ache when the weather is hot like this.---Brian
Title: Re: T head engine by Brian
Post by: Kim on July 28, 2021, 12:37:23 AM
Well, I'm glad you enjoy the heat, Brian.  Looks like we'll be getting a lot more of it going forward! :)

Kim
Title: Re: T head engine by Brian
Post by: Brian Rupnow on July 28, 2021, 01:28:04 AM
Today was a semi quiet day, finishing up little things. The valve seats were cut with my special George Britnel tool. (Actually a larger version of my original tool for valves with 1/8" stems). The valves were lapped into the seats using first 320 grit paste, then 400 grit paste, and finally with 600 grit paste. Then the "handles" were cut off the valves because they were no longer needed. A bronze endcap for the exhaust system was turned, drilled and loctited in place. I found that I had screwed up the design of the valve cages, by not leaving a "tit" of material on the end of the cages to register the springs on. I fixed the design drawing, but rather than remaking the valve cages I turned a couple of "add on" bushings to the end of them with a cavity on one end to fit the o.d. of the valve cages and a cavity on the other end that the o.d. of the valve spring would fit into. The rods hanging out the end of the valve cages are temporary, just in there overnight to ensure correct positioning of the bushings until the loctite sets up. If you don't have this spring locating feature, the spring will ride against the side of the valve stem and cause problems. Tomorrow I will probably make the tappets. I picked up a piece of 01 steel yesterday, long enough to make the tappets and the cams from. ----Both tappets and cams will be flame heated and quenched in oil to harden them.
(https://imagizer.imageshack.com/img922/1930/NIFToZ.jpg)
Title: Re: T head engine by Brian
Post by: Brian Rupnow on July 28, 2021, 07:01:13 PM
Today was tappet day. Doesn't look like much, but these were all machined from a length of 3/4" diameter 01 steel. They will be flame hardened and quenched in oil, as will the cams when I make them. The cams are almost the only remaining part of the valve train to be machined.
(https://imagizer.imageshack.com/img922/8733/OhoF6K.jpg)
Title: Re: T head engine by Brian
Post by: Roger B on July 28, 2021, 07:08:48 PM
Still following in the background, another interesting build  :ThumbsUp:  :ThumbsUp:  :wine1:
Title: Re: T head engine by Brian
Post by: Brian Rupnow on July 29, 2021, 12:01:30 AM
The tappets have been heat treated and assembled and installed in the bushings in the tappet guides. The valves are ground and cut to length, assembled with springs and keepers. I have a couple of sewing needles installed as temporary cross-pins, until I see how everything fits together. I may have to cut one coil from the springs, but I won't hurry to do that. They can always be shortened later. I'm very happy to see that the valve stems line up properly with the tappets.
(https://imagizer.imageshack.com/img924/794/0bAZ0j.jpg)
Title: Re: T head engine by Brian
Post by: Art K on July 29, 2021, 03:09:15 AM
Brian,
You're making good progress, looks like you'll have it running any time. I have to say that I've had a t head engine percolating in the back of my mind. Based on the straight 6 Pierce Arrow series 33 engine. haven't gotten past the thought stage as there is a serious lack of information about it out there.
Art
Title: Re: T head engine by Brian
Post by: Brian Rupnow on July 29, 2021, 11:21:52 PM
Today I have prepared a piece of 01 material to make two cams from. The length of the piece is determined by the depth available in the three jaw chuck which is attached to my rotary table. The center diameter is determined by the maximum bore inside the chuck. The diameters at the ends are equal to twice the 0.382" dimension on the drawing, which determines the size of blank to cut the cam from. The material is just long enough to grip in the three jaw chuck with 3/4" of material stuck up above the chuck jaws. The cams will be .688" long, which should keep the cutter above the chuck jaws. I go a little bit crazy every time I make a cam, because I don't do it often enough to remember all the set-up steps. Attached are the picture of the prepared stock, a drawing of the cam, and a model of the milling machine cutter and the cam in their relative positions on the milling machine. The milling cutter will be turning clockwise, and the center of the mill spindle will be offset from the centerline of the rotary table chuck by 0.346" and 0.200" which, as you will notice on the drawing is the centerline of the flank radius. This should give the cams being cut a 99% chance of matching the drawing. Every time I do this, I write myself a bunch of notes on how to do the set-up, and then read thru all of my notes before I do it again.
(https://imagizer.imageshack.com/img923/294/UnmBAw.jpg)
(https://imagizer.imageshack.com/img922/3338/fHy3C7.jpg)
(https://imagizer.imageshack.com/img922/5232/3fhXZD.jpg)
Title: Re: T head engine by Brian
Post by: Brian Rupnow on July 30, 2021, 05:44:10 PM
Today was not a good day. I fought the cams and the cams won. The cutting tool slipped in the holder. The stock slipped in the chuck.
I was overwhelmed by a truckload of zombies. I was bitten by a rabid bat. I was stung by a murder hornet. My day has turned to crap.  Perhaps a different approach to making cams will be investigated.
Title: Re: T head engine by Brian
Post by: Brian Rupnow on July 30, 2021, 07:32:45 PM
Okay, maybe it's time for some wheeling and dealing. Any of you CNC guys out there want to make me a couple of cams as shown? Surface around outside has to be good quality finish and 3/8" center-hole must be reamed to 3/8" finished size. There are other holes to go in but I can do them later, and I can do the hardening later.  In return, I will send you a complete set of detail drawings to build this engine.----Brian

(https://imagizer.imageshack.com/img922/5008/rAzDFM.jpg)
Title: Re: T head engine by Brian
Post by: Brian Rupnow on July 30, 2021, 11:13:21 PM
A kind gentleman in the USA has volunteered to cnc the cams for me. I am moving ahead working on the crankshaft.---Brian
Title: Re: T head engine by Brian
Post by: Brian Rupnow on July 30, 2021, 11:28:11 PM
I like to make my one piece crankshafts from 1144 stress proof steel. It moves very little while machining, far less than mild steel or cold rolled steel. The only catch is, it is not available in flat-bar. This means that you buy a round piece and machine a flat-bar from it, before you can actually start to machine the crankshaft. I always start by machining one side off in the milling machine, so you have a flat reference to machine or saw away the other side. In this case, I had to machine to a depth of 0.531". Next step will be to saw off the other flat, or flip it over in the milling vice and machine away the other side. Milling is probably as fast as sawing, because my sawblades are always a bit dull, and you end up having to machine that sawed side anyways to get it flat. My mill seems comfortable with 0.015" depth of cut, so that is a lot of cranking back and forth to take off 0.531".
(https://imagizer.imageshack.com/img923/7697/L6vYyZ.jpg)
Title: Re: T head engine by Brian
Post by: Brian Rupnow on July 31, 2021, 09:28:50 PM
Having a lazy day today. When I was reducing the 1144 roundstock for my crankshaft from round to flat the other day, I noticed that the cut was different in one direction than the other in the X axis. This is a sure indicator of a mill being out of tram. I tore down my set-up and got out the steel brake disc that I use for tramming the mill.  Using my coaxial indicator I trammed the mill, then replaced the mill vice and part being worked on. Then I used a 2" face mill to mow away the other side of the round stock, and ended up with a flat bar of 1144 stress proof steel to make a crankshaft from. Not a lot of actual progress, but now I have the material to go ahead and start machining a crankshaft tomorrow.
(https://imagizer.imageshack.com/img924/4215/bwKxHj.jpg)
Title: Re: T head engine by Brian
Post by: Art K on August 01, 2021, 12:34:15 AM
Brian,
I was glad to see you made progress after being g hit by the ten plagues. I haven't done much in the last 6 months and have my own projects so I was glad to see that you found someone to machine your cam. Looking good so far.
Art
Title: Re: T head engine by Brian
Post by: Brian Rupnow on August 01, 2021, 08:36:38 PM
I'm about half way done with the crankshaft. So far, so good. I nailed the center diameter right on, and I'm about 0.001 oversize on the one end thats been turned. That last 0.001" will come off with a 220 grit sanding strip. Now I turn the part end for end, put my "lathe dog" on the finished end, and turn the remaining end to 1/2" diameter. I always triple check myself when I'm about to start carving on a crankshaft.  I've heard far too many "Cut off the wrong piece" stories, and believe me, it's easy to do.
(https://imagizer.imageshack.com/img923/4473/gwhO4X.jpg)
Title: Re: T head engine by Brian
Post by: Brian Rupnow on August 01, 2021, 10:03:50 PM
It's suppertime, and I have a finished crankshaft. It needs a couple of keyways, and I will add them tomorrow.
(https://imagizer.imageshack.com/img924/8877/a0cGvd.jpg)
Title: Re: T head engine by Brian
Post by: crueby on August 01, 2021, 11:13:28 PM
Blinked and I missed it!  That was quick!
Title: Re: T head engine by Brian
Post by: Brian Rupnow on August 02, 2021, 12:16:21 AM
Crankshaft is in, dummy shaft is out. Crankshaft turns easily, nothing crashes. This is always a milestone event for me, because there are so many tolerances that can add up to cause some kind of internal interference with the crankshaft. I'm not going to put keyways in until I'm absolutely sure what I'm doing for flywheels. If I was rich instead of good looking, I'd buy a pair of flywheels, but at $35 each American, plus the difference in our dollars, plus tax, plus shipping, I'd be paying $100 for two flywheels.
(https://imagizer.imageshack.com/img924/4928/2xcULR.jpg)
Title: Re: T head engine by Brian
Post by: Brian Rupnow on August 03, 2021, 01:35:03 PM
Today I am going to make an aluminum piston. Nothing exotic here, maybe the skirt is a bit longer than usual, but other than that it's a plain old piston. We are going to run cast iron rings on this piston, and this time we are going to make the rings a bit thicker at 0.045" to be an exact match with what George Trimble did in his article on how to make piston rings. The ring radial width will stay at 0.039" same as the rings I made earlier in the summer.
(https://imagizer.imageshack.com/img923/3649/7dg8ht.jpg)
Title: Re: T head engine by Brian
Post by: Brian Rupnow on August 03, 2021, 06:00:13 PM
We have a piston!! Everything went well, piston fits cylinder as I had hoped. I almost had a conniption fit when I went to cut the ring grooves. I couldn't find the special cutter that I had ground for me. I looked in all the usual places, and couldn't find it. Then I cleaned up all my work surfaces and I couldn't find it. Then I looked in all the unusual places, and I found it. Now I remember putting it in an unusual place and thinking "Now, I'll keep that separate so I'll know where to find it next time I need it."  Growing old gracefully!!!
(https://imagizer.imageshack.com/img922/8268/1hJ8OX.jpg)
(https://imagizer.imageshack.com/img923/9479/c8BRDe.jpg)
Title: Re: T head engine by Brian
Post by: Roger B on August 03, 2021, 07:59:18 PM
 :)  :)  :)  :wine1:
Title: Re: T head engine by Brian
Post by: Admiral_dk on August 03, 2021, 09:05:15 PM
Quote
Now I remember putting it in an unusual place and thinking "Now, I'll keep that separate so I'll know where to find it next time I need it."  Growing old gracefully!!!

I can relate more than I care to admit to that sentence ....  :old:

Nice work Brian
Title: Re: T head engine by Brian
Post by: Brian Rupnow on August 04, 2021, 08:07:17 PM
Today was connecting rod day at my house. I don't have much to say about it, but it has eaten up about six hours of my time. It turned out fine. Now I'm going to wash up, then go down to PartSource and pick up a sparkplug, ignition points, and a condenser.
(https://imagizer.imageshack.com/img924/893/gYqEWu.jpg)
Title: Re: T head engine by Brian
Post by: Brian Rupnow on August 05, 2021, 02:11:24 PM
This morning the engine is assembled to check for clearances. Happily, nothing crashes, and the crankshaft can make a full rotation with the connecting rod attached without any clearance issues. This almost completes the major components of the engine, and now it will be a simple matter of installing the cams to complete the valve train. Thanks for having a look.---Brian
sKWOqnj_kLw
Title: Re: T head engine by Brian
Post by: bent on August 05, 2021, 09:11:05 PM
Looks good, Brian!
Title: Re: T head engine by Brian
Post by: Brian Rupnow on August 06, 2021, 12:28:19 AM
Today was ignition points, condenser, and ignition cam day. It also was finish the gas tank day. Everything went as planned. I am going to paint that gas tank and the flywheels, so I probably won't do very much cosmetic work on the brazed joints on the gas filler neck and out-spout. A bit of gloss paint hides a multitude of sins!!
(https://imagizer.imageshack.com/img922/4624/ahdbf1.jpg)
(https://imagizer.imageshack.com/img924/7393/7Gp3RJ.jpg)
Title: Re: T head engine by Brian
Post by: Art K on August 06, 2021, 03:11:20 AM
Brian,
Everything looks good, I'm looking forward to seeing the cams installed!
Art
Title: Re: T head engine by Brian
Post by: Brian Rupnow on August 06, 2021, 11:30:09 PM
I spent the day working on a real job, but tonight I'm having a close look at this engine. I think that other than the flywheels and gear covers, everything is finished. I'm waiting for my cams to arrive, and there is a bit of finessing to connect the cams to the large gears. I don't need the gear covers to start the engine, so this could get exciting pretty soon.  I'm still on the fence regarding the flywheels, but I want to go down to my nut and bolt store and look at something. They have a bin full of casters down there, and I remember seeing some large aluminum casters with rubber bonded to the outer rim. I have some double extra strong schedule 80 pipe here, and if I could machine the rubber off those aluminum casters and put some heavy wall pipe around the aluminum, it might make some nice flywheels.
Title: Re: T head engine by Brian
Post by: Brian Rupnow on August 10, 2021, 11:31:19 PM
A HUGE Thank you going out to Sid from New York and to Laverne Karras from Keswick for the cams they CNC machined for me. Both sets arrived today in the mail, and they are simply marvelous. These cams are just about all I need to finish the t-head engine. guys, I really do appreciate it.--I will use the cams Sid made on this current engine, and the ones Laverne made will be saved for my next engine.-Brian
(https://imagizer.imageshack.com/img922/3439/OaICFC.jpg)
Title: Re: T head engine by Brian
Post by: crueby on August 10, 2021, 11:44:22 PM
That is awesome!  Members here helping each other out, whether with parts, tools, tips, information, whatever, is what really makes this forum special.


 :ThumbsUp:    :ThumbsUp:
Title: Re: T head engine by Brian
Post by: Brian Rupnow on August 11, 2021, 12:06:21 AM
Yes, even I get tied up with other things and machining has to take a back seat. I have however, found the time to make my oil filler spout and drain. It's pretty simple. You take both plugs out, and add oil to the sump until it starts to run out the bottom hole. When it does, then the oil is at the correct level.
(https://imagizer.imageshack.com/img923/7866/gIOpWB.jpg)
Title: Re: T head engine by Brian
Post by: Admiral_dk on August 11, 2021, 01:35:28 PM
You can't be far off from a runner now Brian  :ThumbsUp:
Title: Re: T head engine by Brian
Post by: Brian Rupnow on August 11, 2021, 07:42:05 PM
Someone was asking how I would attach the cam to the large gear. Here it is. The # 4 socket head capscrew goes thru the cam and threads into a tapped hole in the gear. The two 1/16" drills which you can see will be replaced by 1/16" diameter drive pins, which pass thru zero clearance holes in the cam and the gear and are held in place by Loctite.
(https://imagizer.imageshack.com/img924/1634/6UMHyE.jpg)
Title: Re: T head engine by Brian
Post by: crueby on August 11, 2021, 08:56:29 PM
Brian, are the drive pins hardened, or just round stock? Nice way to do it!
Title: Re: T head engine by Brian
Post by: Brian Rupnow on August 11, 2021, 11:49:51 PM
The drive pins are just cold rolled steel. Today was a fun day, attaching the cams to the large gears and reassembling everything to see the valves going up and down. It doesn't sound like much, but I've spent the entire day doing it. I'm well pleased with todays work.---Brian
FQYSKkhT4uw
Title: Re: T head engine by Brian
Post by: Brian Rupnow on August 12, 2021, 05:52:51 PM
Well Rats!!! This morning I drove to everywhere in Barrie that sells casters, looking for a caster with an aluminum hub and flange with a cast in place outer sleeve of rubber or nylon. Princess Auto had exactly what I need, but not in the size I wanted. If I could have found the right size of caster I would have removed the outer nylon or rubber and mounted a steel outer rim to create "instant flywheel". Since I couldn't find what I wanted, I will now resort to making my own flywheels from what stock I have on hand.
Title: Re: T head engine by Brian
Post by: Brian Rupnow on August 12, 2021, 08:05:51 PM
I think the summer heat may have driven me mad. I just ordered a pair of 4 1/2" cast iron flywheels from Martin Models in the USA. I checked out what material I had to make these flywheels, and I do have it, but seem to be suffering from a case of "lazy ar$e".  If I hadn't picked up the recent design contract for a couple of welding fixtures, I'd have made the flywheels from what stock I have. My good wife just informed me that any money coming from the small design contract should be spent on "Toys for my hobby" and I'm not going to argue with that!!--Brian
Title: Re: T head engine by Brian
Post by: bent on August 13, 2021, 04:09:53 PM
Brain, I've used Martin's iron flywheels once, but was not very happy with the amount of casting "float".  Was able to get a flywheel that looked good on at least one side, but the opposite side had a lot of "wobble" or runout.  May not be as big an issue for you, because both of your wheels have a fairly hidden side?
Title: Re: T head engine by Brian
Post by: Brian Rupnow on August 13, 2021, 04:53:32 PM
I hope that my flywheels are "true", but if not my lathe can machine away a lot of sins. I am now at the "What do I do next" phase of this build. The only outstanding things are the flywheels, the gear cases and the rings and the gaskets. I don't really want to do anything on the cast iron rings until the flywheels have been machined and mounted. This leaves only the gear cases to be machined, so that is where I will start my next round of machining. the two gear cases will have a slight difference, because one has to be cut away on the bottom side to clear the ignition points. This will mean purchasing a foot of 2 1/2" x 1" aluminum flatbar. I'm beginning to get enquiries from old customers about design work. I don't really want to turn them down, because if it worked out right I might buy a real vertical metal cutting bandsaw. The saw I have now is an old wood cutting bandsaw that I modified to cut metal.---It works, but it is very slow.
Title: Re: T head engine by Brian
Post by: Brian Rupnow on August 13, 2021, 10:05:06 PM
Decided to get up off my lazy butt and actually do something this afternoon. I purchased some 2 1/2" x 1" aluminum bar, cut it to two lengths, laid the outline on it with a template, then set it up in my milling vice and used the DRO to position things accurately. The template helps me figure out what I'm doing, and gives me a visual check, to see if my DRO is giving me the same information. The 0.201" bolt holes were drilled and a 1/2" drill ran thru at the appropriate centers. Next trick will be to mount the pieces one at a time in the four jaw lathe chuck and bore the blind cavities that the gears fit into as well as the thru holes where the gear hubs stick through.
(https://imagizer.imageshack.com/img923/357/4ecR9Z.jpg)
Title: Re: T head engine by Brian
Post by: Brian Rupnow on August 14, 2021, 09:01:44 PM
First I bore the blind hole for the big gear---then I bore the blind hole for the small gear. Then after much sanding, filing, and sanding some more I have an awesome set of gear guards.
(https://imagizer.imageshack.com/img922/8799/Ku0dJ4.jpg)
(https://imagizer.imageshack.com/img922/7430/VuN4qU.jpg)
(https://imagizer.imageshack.com/img922/9834/0uh5cV.jpg)
Title: Re: T head engine by Brian
Post by: Admiral_dk on August 15, 2021, 12:26:37 PM
They do look good and protects small fingers from harm  :ThumbsUp:
Title: Re: T head engine by Brian
Post by: Brian Rupnow on August 15, 2021, 08:30:40 PM
Admiral---They certainly will protect fingers. Oddly enough, that's not the real purpose I put them on there. I find that exposed spur gears make a terrible lot of noise. It seems that if they have a guard made of brass or aluminum (not sheet metal) around them, it quiets them down a lot. and they certainly make the engine look more robust. I am now at the point where I have nothing left to make except the cast iron rings. Earlier this year I did a thread on making my own cast iron rings. There was a great deal of trial and error, but I finally did successfully make a set that worked very well on one of my 1" bore engines. I made a lot of notes about what I did, and I still have all the fixtures I used. This engine is also a 1" bore, so I'm hopeful that I learned enough from my previous ring making exercise to do it again. I'm still waiting to hear from the flywheel people---they are supposed to contact me when the rings are shipped.
Title: Re: T head engine by Brian
Post by: mnay on August 16, 2021, 04:45:33 PM
Brian,
Looks nice.  I always look forward to following your builds.

Mike
Title: Re: T head engine by Brian
Post by: Brian Rupnow on August 16, 2021, 09:18:27 PM
Thanks Mike!! Okay, here's what we've got going. Thats a piece of 1 3/8" diameter grey cast iron in the chuck. The o.d. is turned down to the diameter of the cylinder, not the piston. My rings are going to be .038" (1 mm) thick radially so the inside is drilled out to 0.925" diameter. The o.d  of what will become the rings is polished with a fine whet stone, or a piece of 400 grit paper backed up by a file or piece of flat-bar. This time my rings are going to be 0.045" thick, and my specially ground cut off tool is 0.038" wide, so .045 plus .038 plus .003" to have a bit extra length equals 0.086", so thats how far I advance the carriage before taking another cut. The rod held in the tailstock chuck is something to catch the rings as they are parted off. I have to remember that each time I cut a ring off, I have to deburr the outside and inside diameter of the piece held in the chuck, so that at least one side of the ring is deburred.---It is remarkably easy to forget that step. Each ring will now be measured with my micrometer to make sure it is the right thickness, and then held in a fixture with a 0.020" deep x 1" diameter recess. It is then slid around in a figure 8 on a piece of 600 grit paper until it reaches the magic 0.045" thickness. Then it is fitted into the piston ring groove to make sure that it actually will go down to the bottom of the groove.  My chuck has about 0.003" total indicated runout, so I cut off a bunch of rings while in this set up, because if I take that piece of round stock out of the chuck, I will never get it back in the same spot, and I don't want to make rings that are not truly concentric.
(https://imagizer.imageshack.com/img923/2052/eD1eKu.jpg)
Title: Re: T head engine by Brian
Post by: Brian Rupnow on August 17, 2021, 12:30:21 AM
We're up, up and away!! I managed to harvest ten rings. They were all deburred both sides, and the faces were sanded on 600 grit paper attached to a cast iron surface plate until they were 0.045" to 0.043" thick. They were all spread over a .150" diameter pin and sandwiched and clamped between two sides of a heat treat fixture. They are now in my heat treat oven, soaking at 1100 degrees for three hours. I decided that I didn't really like the "cleaver" that Trimble designed and I built, because it seemed to bend the rings a bit when it cleaved them. I ended up using a sharp cold chisel to "break" each ring, then filed the ends with a points file until they had the correct 0.004" end gap when installed in the cylinder.
Title: Re: T head engine by Brian
Post by: Brian Rupnow on August 17, 2021, 03:26:38 PM
I let the rings cool overnight in the heat treat oven, then this morning I brought the heat treat fixture into my office and disassembled everything. The rings and fixture look rather grotty, but they will all clean up nicely with a small brass brush and running water. You can see that all of the rings have now taken a "set" with the end gap at 0.150" which is the diameter of the post in the heat treat fixture.
I will give the rings one or two small swipes on 600 grit paper to get any residue off the flat surfaces, and give the inside of the rings a bit of deburring with my Dremel tool, then pick out the two I like best and install them on my piston.
(https://imagizer.imageshack.com/img924/74/uvEl5A.jpg)
Title: Re: T head engine by Brian
Post by: Brian Rupnow on August 17, 2021, 05:07:35 PM
Rings are cleaned up and two of them installed on the piston. I don't have a small ring compressor, so I used a trick I learned on one of the forums. Took a piece of 2" round steel x 1" long, drilled and reamed a 1.000" hole through it, then put a 25 degree taper on one side and sanded the transition smooth. Set it on top of the cylinder, started the piston with rings thru it. The 25 degree angle compressed the rings to 1" and the piston sticking out thru the bottom fit into the engine cylinder to line everything up. A few careful taps with a soft faced hammer and the piston with rings slid right into place. Hooked up the con rod to the crank journal, and everything goes round and round very smoothly.
Title: Re: T head engine by Brian
Post by: Admiral_dk on August 17, 2021, 10:44:25 PM
So now we just hope that the compression is as good as your last piston rings (those that worked)  :cheers:

Per
Title: Re: T head engine by Brian
Post by: Brian Rupnow on August 18, 2021, 09:48:40 PM
Today has been a day of cleaning, sanding, and chasing down tight spots. I am always somewhat amazed at how much dirt these little engines make in the final moments of assembly prior to running. A ton of grey sludge seems to come off all of the aluminum parts and even from the cast iron parts. Today I installed the gasket that fits between the two halves of the crankcase and the gasket that fits between the top of the crankcase and the underside of the cylinder assembly. Tomorrow I will make the head gasket and probably make a gasket to put between the cylinder top plate and the cylinder body itself. I haven't heard a peep from the folks at Martin Model about shipping my flywheels, but I see that they have put the charge on my Visa. in a perfect world, I would receive the flywheels before I finish everything on the engine, but it's getting tight. I will set the ignition and valve timing tomorrow, and then there really isn't anything left for me to do. (I say that with tongue in cheek, because I never know until the very last minute if my valves are going to seal or not).
Title: Re: T head engine by Brian
Post by: Brian Rupnow on August 19, 2021, 04:12:17 PM
I spoke with the guy at Martin Models, and he says that my flywheels were shipped out on the 8th of Aug., so hopefully I will see them next week. The engine Gods smiled on me this morning. With the engine all assembled, there was one extremely tight spot in the crankshaft rotation. I measured how far down it was from the top of the cylinder head to the piston when I encountered the hard spot, and took a good look at my 3D model to see if it could tell me anything. It showed a spot between the bottom of the cylinder and the side of the con rod that "might" be tight.--I pulled things apart, and sure enough, there was an interference there. A bit of Dremel tool work got rid of the interference and the crankshaft happily goes round a full 360 degrees with no tight spot. I have a head gasket to make, and then I will set the valve and ignition timing today.
Title: Re: T head engine by Brian
Post by: Brian Rupnow on August 19, 2021, 08:02:09 PM
All right!!!  Engine is timed, both valves and ignition. I didn't use a degree wheel. I set my crankshaft at whatever angle I want in my 3D program, then measure down from the top of the cylinder to the top of the piston. Then I set my vernier for that distance, turn the engine by hand in the correct direction until the piston touches the depth gauge end of the vernier.  Then I loosen off the screws in the crankshaft gear on the side I am timing and rotate it until the valve just begins to open (this is quite visible because the cylinder head is removed).  Ignition timing is set to about 5 degrees before top dead center. I always go a little crazy doing the timing, because I have to remember which side I am putting the starter fixture on, and then remember which side of the engine I'm working with and knowing that on the far side of the engine the crankshaft will be rotating in the opposite direction.
Title: Re: T head engine by Brian
Post by: Bearcar1 on August 19, 2021, 10:19:06 PM
Hi Brian, BC1 here, I've been following along in the shadows the entire time and I like what I see so far. Now I'm not sure about this, but thought I would ask you anyway as there may be others on here that have the same ideas. I have the original drawings that Vederstein produced, but when you are finished, could one purchase a set of your renderings? I have always had a fascination with this odd looking engine and I get almost as much or more enjoyment out of pouring over a set of drawings as I do actually making chips. Forge on my friend and I am looking forward to the first pops as I know you are as well.


BC1
Jim
Title: Re: T head engine by Brian
Post by: Brian Rupnow on August 19, 2021, 11:07:06 PM
Once I have ran the engine and am satisfied that it is a good design, I sell complete plan sets for $25 Canadian. There are between 50 and 60 drawings of individual components and general arrangement drawings showing assembly and part numbers.---Brian
Title: Re: T head engine by Brian
Post by: Bearcar1 on August 20, 2021, 01:23:21 AM
Not a bad deal, what method(s) of payment? Paypal, cashiers check? MO, other?


BC1
Jim
Title: Re: T head engine by Brian
Post by: Brian Rupnow on August 20, 2021, 02:06:23 PM
Paypal to brupnow@rogers.com
Title: Re: T head engine by Brian
Post by: Brian Rupnow on August 21, 2021, 11:16:16 PM
Today I milled keyways into both ends of the crankshaft, finished making gaskets, and mounted the cylinder head and sparkplug. At this point, turning the engine over be hand, I can't really tell if I can feel compression or not. That is not unusual, because my new engines are a bit stiff. Tomorrow we are having a family birthday party for my second oldest granddaughter who is turning 14 and my mother who is turning 101.  There isn't much more that I can do to the engine now until my flywheels come.---Brian
Title: Re: T head engine by Brian
Post by: Bearcar1 on August 22, 2021, 12:08:36 AM
Happy Birthday to your Mother Brian!! Holy Moley!! Tell her Jim Barker still loves her....


BC1
Jim
Title: Re: T head engine by Brian
Post by: Brian Rupnow on August 22, 2021, 07:40:56 PM
Party doesn't start till later in the day. I decided to perform the old, tried and true, "Blow yer Guts Out" test on the engine. This is a simple diagnostic test. You have to sacrifice a spark plug, by chipping out all of the porcelain and soldering a small tube to the sparkplug to which a piece of flexible gas line is attached. This lets you put the other end of the tube in your mouth and "Blow yer Guts Out". In a perfect world, when the engine is at top dead center on the compression stroke and both valves are fully closed (as verified by seeing daylight between the valve stem and the valve lifter), then you shouldn't be able to blow at all. If you can blow, and the air comes out of the exhaust system, then your exhaust valve is leaking. If you cover the end of the exhaust with a finger and you can still blow, then probably your intake valve is leaking. If you cover the intake and the exhaust with your fingers and can still blow, then your rings are leaking. (you have to remove the oil filler plug for the ring test). From what I see today, the exhaust valve and the intake valve are leaking a little bit. The rings don't seem to be leaking at all.  This doesn't surprise me at all, and it is a simple operation to pop off the cylinder head and the top part of the cylinder assembly which has the valve cages in it. A little more dressing with 600 grit aluminum oxide paste will probably fix any current valve leaks.
(https://imagizer.imageshack.com/img923/3079/Ntabiz.jpg)
Title: Re: T head engine by Brian
Post by: Brian Rupnow on August 24, 2021, 03:36:36 PM
After a bit of redressing the valves with 600 grit, everything seems to be sealing okay. Today is going to be an "at the beach" day with one of my grandsons, but I had time this morning to redress the valves. Now it's simply a matter of waiting for flywheels. They were shipped to me on the 8th of August. 16 days and counting---
Title: Re: T head engine by Brian
Post by: crueby on August 24, 2021, 03:54:30 PM
Sounds like a great way to relax while waiting for the carrier pigeons to drag the flywheels up north!
Title: Re: T head engine by Brian
Post by: Brian Rupnow on August 25, 2021, 07:48:05 PM
We took our second oldest grandson and went to the beach yesterday. My God it was beautiful. A lovely lake, bright sunshine, hot temperatures around 80F. Beach wasn't crowded, water was clear. I sat back in my beach chair between swims and thought----My God, if I had to do this every day, I'd go stone crazy. I wish it wasn't so. If I could be happy doing that, I'd sell my house in Barrie and buy a house on a beautiful fresh water lake in the Muskokas, about 30 miles north of where I am. My wife thinks she would like that, but I'm sure that after a couple of months she would be as crazy as I am.  I know!!  Thirty years ago I bought a cottage on one of those beautiful lakes. It was in pretty rough shape. I worked every day for a year on it, with help from our two boys, and we made it a lovely cottage. The week after we finished it I was going nuts trying to find something to do.---So we sold it.  Been down that path before---
Title: Re: T head engine by Brian
Post by: Brian Rupnow on August 26, 2021, 03:22:07 PM
This morning, for something to do, I hooked up the battery to my coil and sparkplug tester to verify that the timing was right where I wanted it to be----it was. I started checking around for Traxxas 4033 carburetors and concluded that I didn't have any, so I ordered three new ones from Ebay. I can and have built my own carburetors in the past, but the 4033 Traxxas carb works so well on these 1" bore engines that it isn't worth the bother to build my own carbs.
Title: Re: T head engine by Brian
Post by: Brian Rupnow on August 26, 2021, 04:48:17 PM
Moving on up---Thirteen years ago, when I first started building model engines, I needed a bandsaw. Metal cutting bandsaws were simply beyond my price range, so I bought a 16" vertical wood cutting bandsaw for $200 and added a second jackshaft and pulleys to slow it down to metal cutting speed, and it has served me faithfully.--It does the job, and does it very well but it's slow. I recently had an old customer come forward and ask me to design a couple of welding fixtures for one of the big three auto companies, and this will leave me with a few thousand dollars that weren't earmarked for anything. I've spent the morning on the telephone calling used machinery dealers, and I may have found a good used metal cutting bandsaw that was designed to cut metal, not wood. This is rather exciting for me, and I'm waiting for a call back from someone in Toronto right now. So----If it works out right, I may have a real, honest to God metal cutting bandsaw in my garage.
Title: Re: T head engine by Brian
Post by: Brian Rupnow on August 26, 2021, 07:35:56 PM
My flywheel showed up in the mail today, and it's a beautiful thing. Only problem is, I bought and paid for two flywheels, not one. I have let Gary at Martin Model know that I've only received one, and I'm sure he will make it right.
(https://imagizer.imageshack.com/img923/1037/IMaODK.jpg)
Title: Re: T head engine by Brian
Post by: crueby on August 26, 2021, 08:23:26 PM
Woo Ho....ooo...  Well swarf-it-all!  Hope the band-saw purchase goes better!   I am sure Martin will make it right, it just wastes time.

Title: Re: T head engine by Brian
Post by: bent on August 26, 2021, 08:34:34 PM
That's a nice looking flywheel.  :cheers:
Title: Re: T head engine by Brian
Post by: Brian Rupnow on August 26, 2021, 09:44:16 PM
Well Sir!!!--That looks nice. The keyway is going to be problematic. My keyseating set has an insertion tool for hubs that are 1" long, while this actual hub is 1 1/4" long. If I try to put a keyway into this hub with my current set up, it will break the broach, to the tune of $100 per. Tomorrow I will machine a longer insertion tool. The proportions of this flywheel are about perfect. Somebody asked if this engine really needs two flywheels. Perhaps not, from a purely mechanical standpoint, but for the sake of art, it needs two. I have never envisioned this engine with only one flywheel.
(https://imagizer.imageshack.com/img922/1984/TGfutu.jpg)
Title: Re: T head engine by Brian
Post by: Art K on August 27, 2021, 02:32:51 AM
Brian,
That engine with the flywheel installed looks mighty fine. Won't be long now!
Art
Title: Re: T head engine by Brian
Post by: Brian Rupnow on August 27, 2021, 06:18:50 PM
Every day we get a little closer. Keyway and grub screws are in flywheel, and a starter hub has been turned and installed. Jeez, I wish I had the other flywheel!!!
(https://imagizer.imageshack.com/img922/2320/Tj5Fcr.jpg)
Title: Re: T head engine by Brian
Post by: Roger B on August 27, 2021, 07:25:03 PM
Looking good and awaiting the first run  :)  :)  :wine1:
Title: Re: T head engine by Brian
Post by: Jasonb on August 27, 2021, 07:34:22 PM
You could always see if it will run with just the single flywheel, may need a slightly faster idle :stickpoke:

And if it does then you will have a spare flywheel ready for the next engine :)
Title: Re: T head engine by Brian
Post by: Bearcar1 on August 28, 2021, 01:03:27 AM
I was thinking the exact same thing Jason, and maybe turn up a flat belt pulley for the other side. Man I would be itching to get that sucker fired off.  :insane:


BC1
Jim
Title: Re: T head engine by Brian
Post by: Brian Rupnow on August 28, 2021, 01:21:28 AM
Tomorrow my wife is having a benefit yard and bake sale to aid in the fight against Parkinsons disease, and I have been told that I WILL help. She only does this every three or four years, and it takes up a whole day (with two months of preparation). Today I went to Toronto and bought a used DoAll industrial metal cutting bandsaw and the VFD required to run it--It is huge, and I haven't even started to figure out how I will get it out of the back of my truck. We are having two grandchildren sleep over tonight to help drag all the yard-sale treasures out of my basement, storage area and garage and get them set out in the driveway early in the morning.
Title: Re: T head engine by Brian
Post by: Art K on August 28, 2021, 02:58:21 AM
Brian,
If it wasn't an 11 1/2 hour drive across a border that's probably closed I'd loan you my chain hoist. I am starting to think you should try to start it with 1 flywheel. The anticipation is starting to set in.
Art
Title: Re: T head engine by Brian
Post by: Brian Rupnow on August 28, 2021, 11:06:08 PM
The yard sale/ bake sale was very successful.  Children and grand children all showed up and helped drag about two thousand pieces of valuable junk out into the front yard and driveway. At the end of the day we had about one thousand pieces of junk left and about $550 profit, which all goes to the Parkinsons foundation. Good wife will spend the next two weeks harassing all of the cheap and free places that help the poor to take the last thousand pieces of junk off our hands. I found time for some measuring. My garage door opening  is 82" high clearance from the floor. The area where I would like the bandsaw to fit has 84" clear from the floor to the underside of a boxed furnace duct. The bandsaw is 72" tall. I don't know how high my cherrypicker engine hoist will reach, and I'm too tired to find out tonight. Tomorrow will tell whether "Rupnow Hoisting Service" is going to be able to get some daylight between the bottom of the saw and my truck bed, or if I'm, going to have to pay some money to get a real hoisting service to come and see me.
Title: Re: T head engine by Brian
Post by: internal_fire on August 28, 2021, 11:49:58 PM
A DoAll is certainly a serious bandsaw. Does it have the blade welder built in?

Good luck with the move-in!

Gene
Title: Re: T head engine by Brian
Post by: Brian Rupnow on August 29, 2021, 12:38:58 AM
Gene--It actually has two blade welders. I don't have it unloaded from my truck yet, but will put up some pictures once it is unloaded.
Title: Re: T head engine by Brian
Post by: Brian Rupnow on August 30, 2021, 03:03:36 PM
Okay--All bandsaw reference has been moved over to a new thread titled "DoAll Bandsaw for Brian". I heard from my flywheel guy in Arizona and he is shipping my second flywheel out today. My new Traxxas carburetors are supposed to get here on 07-September. This build will continue, hopefully to a happy conclusion after I get these two parts. I will use the intervening time to get my new bandsaw set up and running.---Brian
Title: Re: T head engine by Brian
Post by: Brian Rupnow on September 02, 2021, 06:41:52 PM
Having a quiet day today. Can't do any more on the new bandsaw until my electrical friend comes over to wire up the VFD. Can't do very much on the t-head engine until my second flywheel comes or my carburetors come.---However, one thing I needed for the engine was a "starter spud" that fits into my variable speed hand drill for starting the engine with. So----This is my big machining contribution for today.---A starter spud!!!
(https://imagizer.imageshack.com/img923/9087/RzxLYp.jpg)
(https://imagizer.imageshack.com/img922/4482/cbapJz.jpg)
Title: Re: T head engine by Brian
Post by: Brian Rupnow on September 02, 2021, 07:21:29 PM
Yayyy---My carburetors showed up!! Went to take out the garbage and there was the package laying on my front step. Here's a little something to chew on---these carb's are $36 each, American. I bought three. That comes to $108 American. By the time I paid shipping, tax, and the difference in our dollars, it cost me $176 Canadian. Sure ain't cheap to live in the land of the polar bear!!!---Brian
(https://imagizer.imageshack.com/img922/4295/WosOTp.jpg)
Title: Re: T head engine by Brian
Post by: Art K on September 03, 2021, 02:15:19 AM
Brian,
It's looking like a real engine, Have you tried to see if it will pop? or are you going to wait till the other flywheel?
Art
Title: Re: T head engine by Brian
Post by: Brian Rupnow on September 04, 2021, 12:18:20 AM
My second flywheel arrived today. As soon as it came, I grabbed it and ran down to my lathe and machined it. It's a beautiful thing!!!--Still needs a keyway and grub-screws, but maybe tomorrow-----
(https://imagizer.imageshack.com/img924/9108/b3d1KC.jpg)
Title: Re: T head engine by Brian
Post by: crueby on September 04, 2021, 12:26:37 AM
Great!!   :popcorn: :popcorn: :popcorn:
Title: Re: T head engine by Brian
Post by: Brian Rupnow on September 04, 2021, 03:19:05 PM
This is the part where I never know what is going to happen next. The second flywheel has been keyseated, grub-screwed and installed. I have had some engines start right up at this point, amazing and delighting me. I have had engines that ran, but needed considerable tweaking before they ran well. And I have had engines that wouldn't run at all, because something was out of adjustment, the valves leaked, because I had machined something wrong, or perhaps the small engine Gods were just messing with me.---Wish me luck!!!---Brian
Title: Re: T head engine by Brian
Post by: Brian Rupnow on September 04, 2021, 03:58:47 PM
Okay---this one isn't going to take right off and surprise me. Fuel is getting ignited, cylinder is getting warm from firing. I'm not feeling a lot of compression here. The old "oil down the sparkplug hole" trick isn't bringing the compression up any, so this infers that the rings are doing their sealing alright. I will check again to make sure that there is daylight between the valve stem and the lifter when the lifter isn't up on the cam. (this will hold the valve open and no compression will be developed.) Since it does seem to be firing more or less consistently when driven by my electric drill, I will now put an electric motor to driving it, and see if the valves will seal up from the pressure created by the engines firing. if it wasn't firing at all, I wouldn't do this.
Title: Re: T head engine by Brian
Post by: Brian Rupnow on September 04, 2021, 05:27:44 PM
It seems that I have a leaking exhaust valve. Rather than screw around with everything bolted to the engine, I have made a "dummy cylinder" to bolt the cylinder head to. It is an exact copy of the cylinder, but without the center hole for the piston. First thing to check is whether the valve can be rotated into a position that doesn't leak. That technically shouldn't happen, but it sometimes does. Without changing anything on this set up, I can seal the leaking exhaust with my thumb and thus check the intake valve for leaking. I know that I used this same piece of equipment with the "blow yer guts out" test to see if the valves were leaking or not. They didn't seem to be then, but everything gets handled a great deal between that test and when the engine is finished. Today I will test things at 40 psi.
(https://imagizer.imageshack.com/img924/1512/BBq7FU.jpg)
Title: Re: T head engine by Brian
Post by: Brian Rupnow on September 04, 2021, 07:08:17 PM
Compression has improved. Engine is now firing regularly along with power drill as I attempt to get it to take off and run on it's own. Cylinder is getting hot from firing. I am now going to take my degree wheel and check the ignition timing. The common knowledge out there is that four cycle engines should fire about 20 degrees before top dead center. Lots of puffs and snorts from the engine but haven't found the sweet spot yet.
Title: Re: T head engine by Brian
Post by: crueby on September 04, 2021, 07:19:23 PM
Sounds like great progress, looking forward to seeing it go!

Title: Re: T head engine by Brian
Post by: Admiral_dk on September 04, 2021, 07:50:11 PM
It sounds like you are getting very close to a runner  :ThumbsUp:

It might be one or a few minor details that are the last difference between a great runner and one is trying - as you know - so I hope that you find those soon  :cheers:

Per
Title: Re: T head engine by Brian
Post by: Art K on September 04, 2021, 10:06:35 PM
Getting real close now!
Art
Title: Re: T head engine by Brian
Post by: Brian Rupnow on September 04, 2021, 11:08:18 PM
No joy today. Very, very close, but no engine running on it's own. I'm having some kind of compression issue, and I think it is in the valves. Tomorrow I will reset the valve timing with my degree wheel, but my gut is saying it's a valve sealing issue.
Title: Re: T head engine by Brian
Post by: Jasonb on September 05, 2021, 07:31:09 AM
My engines tend to run a 5 to 10deg BTDC, your 20deg sounds a bit early to me particularly for these slow running types.

That way you are more likely to get all the explosive force pushing the piston down, too early and that force is pushing down on the piston while it's still coming up and on it's own the engine does not have the power to overcome that. Also tends to cause more backfires but you won't be seeing that pushing it round with an electric drill, I see it more as mine get started by flicking the flywheel or a short pull cord.

EDIT I just looked at what hamilton Upshur suggests for his Tee Head and it says "a little Before TDC" which I would take as less than 20deg, also suggests 0.010" points gap.
Title: Re: T head engine by Brian
Post by: Brian Rupnow on September 05, 2021, 02:33:53 PM
This morning I am waiting around for my electrical friend to come over and wire up my VFD to run my new bandsaw. I thought "Right now, while my t-head engine is cold, I'm going to try something." I turned it over by hand, and there is very little or no compression. After fooling with it all day yesterday, the engine has loosened up considerably, and I can feel the compression (or lack of) when turning the engine by hand. Pulled out the sparkplug, squirted some oil into the cylinder and then replaced the sparkplug. Surprise!!! Engine now has scads of compression!!--I have a lifetime supply of viton o-rings, and it only takes me a couple of hours to make a piston. Before I go screwing around with the valves any more, I am going to quickly make a new piston fitted with a viton o-ring. If that fixes things, I will revisit my cast iron rings.
Title: Re: T head engine by Brian
Post by: Bearcar1 on September 05, 2021, 09:17:00 PM
save your breathe Jason. :toilet_claw:
Title: Re: T head engine by Brian
Post by: Brian Rupnow on September 05, 2021, 11:16:41 PM
Bearcar---that is a very strange post. I read all of the responses to any thread I start. I don't always immediately run and do what people suggest. Sometimes I do, sometimes I don't necessarily agree with the poster and I don't.  I'm not looking to start a flame war with anyone. Sometimes I will post my immediate thoughts on what I plan on doing next, sometimes when I've thought about it for a while I decide to approach the problem a different way. :pinkelephant: :pinkelephant: :pinkelephant: Before I make a new piston I am going to check my valve timing with a degree wheel. The valve timing was initially set using measurements from the top of the cylinder down to the top of the piston, taken from my 3D model when the crankshaft was positioned at the correct number of degrees before top or bottom dead center. I will certainly check the valve timing again with a degree wheel just to be absolutely sure of it.
Title: Re: T head engine by Brian
Post by: Brian Rupnow on September 06, 2021, 05:30:49 PM
Okay Kiddies---It's showtime. Yesterday I had worked my way right into a snit trying to get this engine to run. I was almost at the point of making a new piston with a viton ring to get more compression. I decided that before changing anything, I would bring the engine in from my big garage and use a degree wheel to set the valve timing exactly "on spec" and to reset the ignition timing to about 12 degrees before top dead center.--I discovered that the grub screws in the gear which drives the exhaust valve had backed off and the exhaust valve timing was way out of whack.  So, in the end, I really didn't change anything. The engine runs very well, and after playing with it a bit as "final tuning" I will reinstall the gear covers and clean everything up.   If you would like to build this engine, I sell a complete plan set of engineering drawings, including detail drawings and assembly drawings for $25 Canadian funds, paid to Paypal to brupnow@rogers.com    Thank you to everybody who followed the build, and thank you for your posts and the information you have given me.---Brian Rupnow
O_kE2aVUvWc
Title: Re: T head engine by Brian
Post by: crueby on September 06, 2021, 06:53:12 PM
Super!!   :cartwheel: :whoohoo:
Title: Re: T head engine by Brian
Post by: Don1966 on September 06, 2021, 07:02:22 PM
Awesome….. :pinkelephant:


Don
Title: Re: T head engine by Brian
Post by: Admiral_dk on September 06, 2021, 07:15:15 PM
Great to see and hear it run - congratulations Brian.

So what is next ?
Title: Re: T head engine by Brian
Post by: Brian Rupnow on September 06, 2021, 07:47:08 PM
If I'm bored next week, I may make a cooling fan for it. This won't be anything new, it will be very similar to the cooling fan I made for my vertical engine. These fans put out a lot more wind than you would think. When the engine is running at 1000 rpm, the fan is turning at about 5600 rpm.
(https://imagizer.imageshack.com/img924/1244/d1N1Xh.jpg)
Title: Re: T head engine by Brian
Post by: Trevorc on September 06, 2021, 08:57:40 PM
Well done Brian, I am envious of your skill and productivity.
Trevorc
Title: Re: T head engine by Brian
Post by: Brian Rupnow on September 06, 2021, 09:52:00 PM
Thank you guys. Here is the true story of the cam and valve timing that I use for all of my gasoline engines. This cam is longer than the most cams are, but the profile is exactly the same. I use the same profile for both intake and exhaust valves. I use this profile for flathead, T-head, overhead valve and overhead cam engines. It works fine for all of them. You can see on the drawing that only 120 degrees of this cam has any effect on the lifter or pushrod. Since there is a 2:1 ratio between the camshaft and crankshaft, that means that this cam actually has 240 degrees of influence on the engine. I set my exhaust valve to begin opening 40 degrees before the piston reaches bottom dead center on the power stroke. Due to the cam profile, the exhaust valve will begin closing 20 degrees after top dead center on the intake stroke. The intake valve begins to open 15 degrees before top dead center on the exhaust stroke, remains open throughout the entire intake stroke, and closes 45 degrees after bottom dead center on the compression stroke. The ignition timing is set to spark 12 degrees before top dead center on the power stroke.
(https://imagizer.imageshack.com/img924/3253/jIrfhJ.jpg)
Title: Re: T head engine by Brian
Post by: Brian Rupnow on September 07, 2021, 01:28:02 AM
Tomorrow I am going to try something new. In the attached model, you can see that there is a blue fan shaft support plate setting on top of an existing gear guard. There is no good way to bolt this onto the gear guard. I have modelled a completely new gear guard which has the fan shaft support integrated into it, but I don't have material to make it that way. Tomorrow I am going to buy some "alumiweld" brazing rod and attempt to weld that blue piece to the existing gear guard. I can buy two rods for $10 at Canadian Tire. If I fail, I'm only out $10. It would probably take about $15 worth of material to make a new one piece gear guard combined with fan shaft support. I've been wanting to try this method of welding aluminum, but haven't had any real reason to until now. I will let you know what happens.---Brian
(https://imagizer.imageshack.com/img924/1244/d1N1Xh.jpg)
Title: Re: T head engine by Brian
Post by: Art K on September 07, 2021, 03:41:03 AM
Whoo Hoo... happy dance time. :pinkelephant: :cartwheel:
Great to see it run!
Art
Title: Re: T head engine by Brian
Post by: Brian Rupnow on September 07, 2021, 06:30:13 PM
This is one of the gear guards with the new fan shaft support tab setting in place beside it. I chickened out on using the 'alumiweld' brazing rods and instead went to my welding supply shop and bought some 3/32" aluminum rod to use with my tig welder. I will practice a bit on some scrap aluminum pieces, and then weld the two pieces in the picture together. Tig welding with aluminum is a skill I have to develop, and I might as well start now. I will post the end results of this tig welding.
(https://imagizer.imageshack.com/img924/9555/5fSapD.jpg)
Title: Re: T head engine by Brian
Post by: Brian Rupnow on September 07, 2021, 11:49:34 PM
Well, there we have it. My first tig weld on aluminum. Aluminum is definitely a different kind of thing to weld than mild steel. One of the biggest problems was that the people who sell this welder in Canada are a bunch of morons. They sell the welders in Canada but don't have any kind of technical help. I called Toronto and asked for a tech help guy, and they shuffled me around from person to person, and finally I got a guy who moaned and groaned like he was in hard labour birthing an elephant, and after about ten minutes I said "Tell me the truth. You've never welded anything in your life, have you." He reluctantly told me that no, he wasn't a welder but he had read a lot of manuals.  I hung up and called the company in Orillia that sell these machines, and got a bit of help from them. I had first tried to weld with the frequency control button off, because I didn't know any better. Once I had it turned on, things got marginally better.  What I found was, that my welds were majorly ugly.---Like really ugly!! I kept at it until I could see that I was getting penetration on both pieces, and since the welds were so ugly, I laid down a lot more weld than I needed to, so that when I ground 90% of it off the part wouldn't have craters in it. It really doesn't look too bad.  The good thing here is that this part will be pretty well hidden behind the fan and the flywheel, so if it's not exactly a work of art it won't matter that much. There must be an awful lot of practice involved between what I did today and those guys on Youtube who are tig welding aluminum and "stacking dimes".
(https://imagizer.imageshack.com/img923/8463/qLU7Mb.jpg)
(https://imagizer.imageshack.com/img923/7586/jWlJmT.jpg)
Title: Re: T head engine by Brian
Post by: crueby on September 08, 2021, 12:07:42 AM
For being self taught on the welding, looks like you are doing well, looks fine to me after being ground down. Definitely an art to the welding, one of these days I'm going to take some classes on it at the local welding shop where they have real welders teaching at their school building out back of the shop. Those 'tech support' ninnies need to have that elephant pulled out of thier nose. Or worse!

 :cheers:
Title: Re: T head engine by Brian
Post by: MJM460 on September 08, 2021, 12:17:48 PM
Great to see it running so well Brian, after the saga of the rings, I am glad the initial problem was something simple.  And clearly the effort on the rings paid off.

Congratulations.

MJM460

Title: Re: T head engine by Brian
Post by: Brian Rupnow on September 09, 2021, 01:55:32 AM
NJM460---Nice to hear from another Ontario guy. Thanks for looking. I spent this morning working on a real job (to pay for my DoAll bandsaw). Then I spent this afternoon running all over town trying to buy stuff that nobody in Barrie carries. Then I machined the little bits and pieces that make up my fan.  My local bearing supply shop has changed their policy to a $25 minimum charge for anything bought at the store. They have lost me as a customer. The sealed bearings in the picture are 3/16" i.d. router bearings from Busy Bee Tools.  My friend the electrical wizard is coming tomorrow to help me sort out the bandsaw VFD. next thing for the engine is to make a fan blade.
(https://imagizer.imageshack.com/img923/4148/zakbl8.jpg)
Title: Re: T head engine by Brian
Post by: Brian Rupnow on September 09, 2021, 10:44:25 PM
Today I machined a fan, and done something dumb. The fan and pulley are silver soldered together, and the hub has a recess for two ball bearings and a spacer. They are in a blind hole, and all of my reamers have a chamfer on the end. To get around having a chamfer in there, I cut the counterbore with a 3/8" endmill. Dumb move. A 3/8" endmill cuts a hole about 0.010" oversize, enough to make the hub go all "wobblycock" on the bearings. My fix is to mount the fan and hub in the 3 jaw chuck, and mount the fan shaft and bearings in the tailstock chuck. Liberally coat o.d. of bearings and spacer with J.B. Weld, then advance the tailstock ram until everything is where it should be linearly. If I've lived a good clean life (Ha-Ha), everything should be aligned when  get up tomorrow.
(https://imagizer.imageshack.com/img924/4781/MnWdkc.jpg)
Title: Re: T head engine by Brian
Post by: Brian Rupnow on September 10, 2021, 01:24:26 PM
This morning I brought all the drawings up to date and saved them as .pdf files. There are 43 drawings, and some have multiple sheets, so there are about 50 drawings in all. Each component has a detail sheet, and the main overall assembly has parts lists and identifying part numbers and bills of material. I have a bit of finish work to complete on the fan components, but the drawings are complete and included in the package. I sell a complete set of these drawings for $25 Canadian funds, paid to Paypal to brupnow@rogers.com  ---Brian
Title: Re: T head engine by Brian
Post by: Brian Rupnow on September 10, 2021, 08:32:29 PM
Today was painting day. I picked up a can of orange Tremclad paint, because that was the only color that I hadn't used already. The fan can be flat back, it's not that important. The aluminum gear covers didn't really need to be painted, but there were enough dings and low spots in them that I filled all the low spots with J.B.Weld yesterday, sanded it smooth this morning and gave them a double coat of aluminum paint. I wish there was a filler that matched the raw aluminum color exactly, but if there is I don't know about it. Now, it seems like I've worked myself out of a job for the time being, so the rest of the day will be spent doing not much---Ahhhh
(https://imagizer.imageshack.com/img922/4341/cpv4Hg.jpg)
(https://imagizer.imageshack.com/img922/8735/HFqrb4.jpg)
(https://imagizer.imageshack.com/img923/559/J6u37H.jpg)
(https://imagizer.imageshack.com/img923/7040/HnmHOw.jpg)
(https://imagizer.imageshack.com/img922/7039/OMdbTx.jpg)
Title: Re: T head engine by Brian
Post by: Brian Rupnow on September 10, 2021, 10:17:34 PM
James---I just come in from mowing the lawn and seen a notification from Paypal. Congratulations!! You are the first to build this engine, other than me. There is always something special about being first, but if I left off any dimensions, you will be the first to discover them. Good luck.---Brian
Title: Re: T head engine by Brian
Post by: Bearcar1 on September 10, 2021, 10:57:32 PM
Thank you so much Brian, I guess that makes mine serial number 0002.  :ROFL:  Files are DLed and am in process of securing them now (backing up etc) 43 pages worth and those bad boys are looking good!  :Love:  I will be up half the night arm chair machining this beast.  :atcomputer: Thanks again!  :DrinkPint:


BC1
JIM
Title: Re: T head engine by Brian
Post by: Craig DeShong on September 11, 2021, 01:52:54 PM
Okay Kiddies---It's showtime. Yesterday I had worked my way right into a snit trying to get this engine to run. I was almost at the point of making a new piston with a viton ring to get more compression. I decided that before changing anything, I would bring the engine in from my big garage and use a degree wheel to set the valve timing exactly "on spec" and to reset the ignition timing to about 12 degrees before top dead center.--I discovered that the grub screws in the gear which drives the exhaust valve had backed off and the exhaust valve timing was way out of whack.  So, in the end, I really didn't change anything. The engine runs very well, and after playing with it a bit as "final tuning" I will reinstall the gear covers and clean everything up.   If you would like to build this engine, I sell a complete plan set of engineering drawings, including detail drawings and assembly drawings for $25 Canadian funds, paid to Paypal to brupnow@rogers.com    Thank you to everybody who followed the build, and thank you for your posts and the information you have given me.---Brian Rupnow
O_kE2aVUvWc

Nice job Brian, looks like you have another runner  :whoohoo:
Title: Re: T head engine by Brian
Post by: Brian Rupnow on September 11, 2021, 03:09:57 PM
So here we have the engine dressed out in all of it's pretty colors. I had to get my good wife to take the pictures with her cell phone. Right now it is taking better pictures than my $700 digital camera. I will post one more video of this engine running, and then, as Bugs Bunny would have said--"That's all folks!!!"
(https://imagizer.imageshack.com/img924/4985/yCsyY6.jpg)
(https://imagizer.imageshack.com/img924/1168/M8WVhb.jpg)
(https://imagizer.imageshack.com/img924/4615/tJcddG.jpg)
(https://imagizer.imageshack.com/img923/3153/Tmw3WA.jpg)
Title: Re: T head engine by Brian
Post by: Pete49 on September 12, 2021, 04:17:27 AM
Looks good with the paint job as well. Nice little goer.
Title: Re: T head engine by Brian
Post by: Roger B on September 12, 2021, 02:07:35 PM
Very nicely done  :praise2:  :praise2:  :wine1:

I tried some of those aluminium soldering/brazing rods with success. There is quite a small window between the flux and the rod melting and everything melting  ::)

https://www.modelenginemaker.com/index.php/topic,9433.0.html
Title: Re: T head engine by Brian
Post by: steamer on September 12, 2021, 02:15:18 PM
It's a runnah!    Nicely done Brian!

Dave
Title: Re: T head engine by Brian
Post by: Brian Rupnow on September 12, 2021, 03:43:25 PM
Question--do you have to have a special tool to insert helicoils? I have a couple of 10-24 threaded holes in my aluminum cylinder head that are getting kinda funky. I can buy a bag of helicoils for $12, but I I buy a "helicoil kit" the price shoots up to $45
Title: Re: T head engine by Brian
Post by: Roger B on September 12, 2021, 03:47:22 PM
The outside thread may be special  :headscratch: The inserting tool just has a slot in the end to drive the tang in the helicoil so it tends to 'shrink' it as it goes in.
Title: Re: T head engine by Brian
Post by: steamer on September 12, 2021, 03:48:09 PM
I have been successful using just a screw to insert them in a pinch.    You could try it that way and buy the tool if you need it
Dave
Title: Re: T head engine by Brian
Post by: Brian Rupnow on September 12, 2021, 09:13:55 PM
After painting and reassembling the engine, it looks lovely but it won't start. It won't start because it has lost compression at the valves.
It started and ran fine earlier this week. The painting process didn't involve any of the things that would make the valves leak.  Valve timing and ignition timing have been checked, and they are "spot on". The only difference between this engine and other engines I have built is the exceptionally long guided area of the valve stems. I have a theory that the longer contact area is creating enough friction on the valve stem to keep them from closing properly. First and easiest thing to try will be stronger valve springs. If that doesn't fix things, then my other idea can be seen at the right hand valve in the drawing. The lower portion of the guide area of the valve cages would have a clearance from the valve stem, and an inserted, concentric supplementary guide Loctited into the very bottom. This may well be the reason that Vederstein couldn't get the valves to seal on the t head engine that he built.
(https://imagizer.imageshack.com/img924/7795/kGKe0r.jpg)
Title: Re: T head engine by Brian
Post by: john mills on September 12, 2021, 11:27:20 PM
to fit the helical you need the tap it is the same pitch but is a  size so when the insert screws in the inside is the
correct size for the original thread.so the hole has to be retapped with the helical tap.then the insert can be screwed in by a tool with drives it in by the tang  the tool has a slot and is of a size the insert fits over and the tang fits in the slot .when in the tang is broken off by bending .sometimes a light bump on the tang will do
some times the tool will grip sufficiently to bend enough up and down   and it should fall off.
The kit should have the helical tap.
John
Title: Re: T head engine by Brian
Post by: Brian Rupnow on September 14, 2021, 09:33:31 PM
I dipped into the Rupnow fortune today and bought a 10-24 Helicoil kit which comes with all the necessary drills, taps, etcetera and about 40 inserts in different lengths for $116.00. While I was picking up the kit, I picked up some very heavy, bull-doggy looking compression springs to be used as valve springs. The valve springs I have on the engine now are 0.026" diameter wire size. The new ones I bought are 0.049" wire size. They are also larger in overall diameter, so tomorrow I will machine new valve cups that go on the valves to center the springs. This business of valves sealing one day good enough for the engine to run, and then not sealing the next day is ridiculous.
Title: Re: T head engine by Brian
Post by: Brian Rupnow on September 15, 2021, 09:13:56 PM
The Helicoils worked great. I have never used them before and I must say, they work fine and don't require a lot of work to use them.  I did machine new spring cups and install them and the heavy valve springs on the engine, but it didn't really help. I then took the cylinder head off the machine and ran a 0.200" diameter drill up from the bottom side of the valve cages, about 0.6" to cut down on the amount of friction between the valve stems and the valve guide portion of the valve cage. I took the heavy springs and cups off and put the originals back on. I reground the valves. Nothing really helped get my compression back.  Something I have noticed over the years--When the seat portion of the valve cage gets too large, it is almost impossible to get a good valve seal. I'm stumped at the moment. I may machine new valve cages and reface the valves in the lathe, more or less starting over again with the valve sealing issue. I have rechecked the valve and ignition timing, but they are fine.
Title: Re: T head engine by Brian
Post by: Roger B on September 16, 2021, 07:01:17 AM
Are you sure it is actually the valve seat that is leaking and not the joint between the cage and the cylinder head? There is quite a short path to the port.
Title: Re: T head engine by Brian
Post by: Brian Rupnow on September 16, 2021, 03:34:51 PM
I spent all of yesterday flogging a dead horse. Today I am going to make new valve cages and loctite them into the head. A close visual inspection of the existing valve cages shows that the seat area has become too large because of repetitive lapping to get a good seal on the valves. Also, due too the method I used when making them, the seat area is not perfectly centered on the guide area. I tried to take picture to post here, but my digital camera can't get a shot which shows it clearly.
Title: Re: T head engine by Brian
Post by: Brian Rupnow on September 16, 2021, 09:39:47 PM
So, here is a family picture. The cylinder head with new valve cages pressed and loctited in place, the old valve cages which have been pressed out (You can see the excessively large valve seat area in the picture), along with valves, keepers, and springs. I haven't used my special tool for cutting new valve seats into the cages yet, I'll wait until the Loctite dries 24 hours. I am now using my wifes old digital camera, as it takes pictures much more clearly than mine. Design review came back to my customer today on the welding fixtures I designed, and it looks like I will have a full day tomorrow just making all the changes.
(https://imagizer.imageshack.com/img923/5901/bGMPOB.jpg)
Title: Re: T head engine by Brian
Post by: Brian Rupnow on September 21, 2021, 12:29:06 AM
It's been a wild and crazy two weeks since I first had this engine running. I have been very busy changing my shop around to make room for a big DoAll Bandsaw and preparing to sell my smaller metal cutting bandsaw. Strangest thing---the engine ran fine before I painted the flywheels and gas tank, but after the paintjob I couldn't get this thing to run for love nor money. These engines are not terribly powerful, and I was having enough interferance between the large timing gears and the aluminum casings over them to keep the engine from running on it's own. The engine ran again on it's own for the second time about 3:00 this afternoon, and I've been chasing down interferences and tight spots until about 20 minutes ago. The small carburetors from Traxxas are just right for these engines I build, but the throttle is very loose so that it can be operated by a servo. I don't use servos to control my engines, and the default setting is for the carburetor to open the throttle wide open just from engine vibration if I don't have something connected to that throttle. Tomorrow I will post a better video out in my main garage where there is lots of natural light with the garage doors open, and I have a better hook up for the engine throttle.---And yes, that little 10 blade fan being ran from the flywheel by a rubber o-ring puts out an amazing amount of air over the cylinder.---Brian
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Title: Re: T head engine by Brian
Post by: Art K on September 21, 2021, 02:43:04 AM
Brian,
It is good to see that you have sorted out the problems and have the T head running again.
Art
Title: Re: T head engine by Brian
Post by: Brian Rupnow on September 21, 2021, 03:14:48 PM
So this is it kiddies. The engine is completely finished, runs the way I like, and looks pretty too. I had a few problems with valves not sealing, but new valve cages were made and the problem was fixed. This has been an interesting engine to build, and it is similar in many respects to the flathead engine I built ten years ago. Complete plan sets are waiting to be sent out to anyone wishing to build this engine.($25 Canadian funds), contact me. Thanks to all who have followed and commented on the forums as this engine came together.---Brian Rupnow
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Title: Re: T head engine by Brian
Post by: crueby on September 21, 2021, 03:44:26 PM
Love the nice slow tickover, sounds great!
Title: Re: T head engine by Brian
Post by: Brian Rupnow on January 19, 2022, 05:29:05 PM
This is the T head engine I designed and built a few months ago. I finished the engine, tuned it to run and took a video. Then it went up on the shelf. Yesterday I had some free time, so I got it off the shelf, down to my work area, and made up a spring return bracket and a throttle extension handle with a return spring. I started it up, adjusted the idle, and then let the engine run until it ran out of fuel. I had my office door open while this was happening so I didn't gas myself. Actually, I went into my machine shop and worked on something else until I heard the engine quit.
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Title: Re: T head engine by Brian
Post by: ShopShoe on January 20, 2022, 01:35:55 PM
Brian,

Thanks for another look at this one. The spring and lever and the result of their addition makes the engine run the way I like them also.

The sound reminds me of the old generator sets: A constant background sound while going about other chores....

ShopShoe