Another Internal Combustion Engine
- Thread starter Rdean33422
- Start date
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I wrote thread #20 yesterday but I forgot to post it so two for today
Thanks Danuzzo
Cutting out the cam shaft supports.
Hot off the mill.
The cam shaft drive gears can be either helical or bevel gears. The helical gears are more compact but much more expensive and a 2to1 ratio is also rare. I will be using the bevel gears but there are still problems with size. In order to get the pinion gear big enough so I could mount it on the crankshaft I had to go to Mod 1.5 which has good sized teeth on it and that makes the driven gear quite large.
Here is a shot of how I modified the pinion gear to fit a 12mm shaft and shorten it up as much as possible. There isn't much meat left on the inside hole. I was able to shorten the length of the gear considerably but that meant most of the original set screw holes were cut away. I pressed a brass collar over the gear and drilled and tapped through that for the set screw.
The driven gear was reduced in diameter by 1/2" which meant cutting away the outside 1/4"of the teeth. I didn't need the full length teeth for this application anyway.
I mounted the cam supports on the engine and there was just enough room.
The driven gear is only about 0.050 away from the engine base and I now have 0.950 of shaft left for the flywheel.
Quite happy with how things turned out. (maybe I should make my crankshafts longer in the future)
I was turning the engine over with the drill when I realized I had another big problem. Even at 250 rpms the engine wants to leave the shop. I will work on that issue next.
Thanks for looking
Ray
Thanks Danuzzo
Cutting out the cam shaft supports.
Hot off the mill.
The cam shaft drive gears can be either helical or bevel gears. The helical gears are more compact but much more expensive and a 2to1 ratio is also rare. I will be using the bevel gears but there are still problems with size. In order to get the pinion gear big enough so I could mount it on the crankshaft I had to go to Mod 1.5 which has good sized teeth on it and that makes the driven gear quite large.
Here is a shot of how I modified the pinion gear to fit a 12mm shaft and shorten it up as much as possible. There isn't much meat left on the inside hole. I was able to shorten the length of the gear considerably but that meant most of the original set screw holes were cut away. I pressed a brass collar over the gear and drilled and tapped through that for the set screw.
The driven gear was reduced in diameter by 1/2" which meant cutting away the outside 1/4"of the teeth. I didn't need the full length teeth for this application anyway.
I mounted the cam supports on the engine and there was just enough room.
The driven gear is only about 0.050 away from the engine base and I now have 0.950 of shaft left for the flywheel.
Quite happy with how things turned out. (maybe I should make my crankshafts longer in the future)
I was turning the engine over with the drill when I realized I had another big problem. Even at 250 rpms the engine wants to leave the shop. I will work on that issue next.
Thanks for looking
Ray
Maybe you need a big block of concrete to bolt the engine to haha. I suppose the flywheels will help.
Add some balance weights to the crank.
I weighted the connecting rod, piston, and the rod journal bearing together and they came out to almost 5 oz. Now after much deliberation and concentrated thought using several data pages and checking the phase of the moon I came up with the size of the counter weights that I needed to make.
(Really I just guessed)
Cutting the counter weights from some 1/2" thick bronze.
As long as I had the material mounted on the mill I cut out the cam also.
The two weights together are 4.4ozs but they are mounted out further on the crank webbing so it should all even out.
A test at 1000 rpms proved to be very satisfactory.
Thanks for looking
Ray
(Really I just guessed)
Cutting the counter weights from some 1/2" thick bronze.
As long as I had the material mounted on the mill I cut out the cam also.
The two weights together are 4.4ozs but they are mounted out further on the crank webbing so it should all even out.
A test at 1000 rpms proved to be very satisfactory.
Thanks for looking
Ray
It's valve time today but I only got 3 pictures.
One valve in progress.
Both valves with screw on spring retainers along with both intake and exhaust valve guides.
Everything installed with springs and retainers.
The valve on top is the exhaust.
This was a long day in the shop but when you're on a roll you just keep going.
Thanks for looking
Ray
One valve in progress.
Both valves with screw on spring retainers along with both intake and exhaust valve guides.
Everything installed with springs and retainers.
The valve on top is the exhaust.
This was a long day in the shop but when you're on a roll you just keep going.
Thanks for looking
Ray
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I have the mechanism for the exhaust valve installed.
It's the little things that take the longest to make.
I have left the rocker arm extra long for now until I decide where I want the "miss" catch arm to be.
Thanks for looking
Ray
It's the little things that take the longest to make.
I have left the rocker arm extra long for now until I decide where I want the "miss" catch arm to be.
Thanks for looking
Ray
The last couple of days I have been busy in the shop.
I made the magnet wheel for the ignition system and the drive pulley for the governor.
Driven governor pulley mounted in the ball bearing housing.
Rubber belt drive with a 1/4 twist. It tracks just fine thank you.
Catch arm, actuator rod and governor spool made, installed and adjusted.
I need to trim off some material on the cam shaft, the catch arm, and the actuator rod but I want to finish the fly ball assembly first.
If everything works as I hope it will then I will dissemble the engine for painting. I still need to drill the head bolt holes.
Anyone have a preference for the color?
I'm leaning toward orange.
Thanks for looking
Ray
I made the magnet wheel for the ignition system and the drive pulley for the governor.
Driven governor pulley mounted in the ball bearing housing.
Rubber belt drive with a 1/4 twist. It tracks just fine thank you.
Catch arm, actuator rod and governor spool made, installed and adjusted.
I need to trim off some material on the cam shaft, the catch arm, and the actuator rod but I want to finish the fly ball assembly first.
If everything works as I hope it will then I will dissemble the engine for painting. I still need to drill the head bolt holes.
Anyone have a preference for the color?
I'm leaning toward orange.
Thanks for looking
Ray
I like the little turnbuckle adjuster!
Doug
Doug
danallen
Well-Known Member
I am a fan of green with yellow accents.
That was left over from my ultralight days Thanks.
I had thought of that too. thanks
Some of the governor parts.
And two views of the governor all assembled and installed.
I will have to get a stiffer preload spring and maybe a smaller drive pulley as the weights really fly out.
I am happy with the way it works so a couple of adjustments and it is ready to go.
I am going to disassemble the engine and paint it either red, orange, or blue. (or Green)
Still haven't decided.
Thanks for looking
Ray
The red and green spray paint cans were almost empty and the blue just wasn't doing it for me so Allis Chalmers orange it is.
I took a couple of hours to shine up some of the aluminum pieces.
On just about every model I have made I don't let the paint dry long enough and end up messing it up somewhere.
I have other obligations to do tomorrow so may not get any shop time on the engine.
Maybe the paint will be dry Friday.
Thanks for looking
Ray
I took a couple of hours to shine up some of the aluminum pieces.
On just about every model I have made I don't let the paint dry long enough and end up messing it up somewhere.
I have other obligations to do tomorrow so may not get any shop time on the engine.
Maybe the paint will be dry Friday.
Thanks for looking
Ray
The paint hadn't completely cured today so I put the pieces in the toaster oven for a few minutes.
While I was waiting on that I decided to cut the o-ring groove in the piston. I didn't have any o-rings the right size for this larger piston so I had ordered some from Graingers. I wanted 75 shore hardness and the calculated size in Viton rubber. I had looked in Mc-Master Carr for them but the smallest quantity they offered was 25. I don't think I will ever use 25 o-rings of this size. Graingers had a package of 10 and since I could pick them up from the store I went with them.
I should have read the description a little closer as these turned out to be square o-rings and I had never used that type before. Who knows they may be better for this application.
A couple of pictures of the current progress all shined and painted up.
The compression seems good but I won't know for sure until the head is installed.
Do you like the shiny water jacket top?
I will be gone for the next week or so cruising the Bahamas.
Thanks for looking
Ray
While I was waiting on that I decided to cut the o-ring groove in the piston. I didn't have any o-rings the right size for this larger piston so I had ordered some from Graingers. I wanted 75 shore hardness and the calculated size in Viton rubber. I had looked in Mc-Master Carr for them but the smallest quantity they offered was 25. I don't think I will ever use 25 o-rings of this size. Graingers had a package of 10 and since I could pick them up from the store I went with them.
I should have read the description a little closer as these turned out to be square o-rings and I had never used that type before. Who knows they may be better for this application.
A couple of pictures of the current progress all shined and painted up.
The compression seems good but I won't know for sure until the head is installed.
Do you like the shiny water jacket top?
I will be gone for the next week or so cruising the Bahamas.
Thanks for looking
Ray
I will be interested in your experience with the quad rings. I have tried both styles without seeing any difference. I have talked to some who like them and some that don't.
Thanks Dan
Much of this build has been an experiment for me from the side shaft to the steel cylinder liner and many more things. So far the square o-ring seems to be doing fine.
Ray
