Design and build side-shaft hit and miss engine from bar stock

[Brian Rupnow]

As promised, here is the new carburetor drawing. It actually has a total of four sheets to it. I am posting an image of the first page here. The full four pages can be downloaded from the attached link.---Brian

http://www.mediafire.com/file/7b03o2fo3b9bfns/CARBURETOR_0.156_RUPNOW_WITH_OFFSET.JPG/file

 

[Brian Rupnow]

Here we go---Final video time. This has kept me entertained/drove me crazy since mid December, and I'm not sorry to be leaving it behind. Thanks very much to all of you who followed this long post. I have learned a lot on the way, and discovered a couple of new things, and now I will leave it behind.---Brian Rupnow

 

[Johno1958]

Good on you Brian she runs very well and I can hear the miss action. No doubt about it you put in the long hard yards and you got a lovely runner.
Cheers
John

 

[JohnBDownunder]

No!
Thank You Brian.
If you had not posted your adventures / misadventures in building this engine I feel we would all have missed a great thread and learning experience.
You sure made some modifications along the way, some worked, some didn't, but all made for interesting time in front of the computer even down here in OZ.

John B

 

[DavidLloyd2]

Very nice engine Brian

DavidLloyd

 

[Brian Rupnow]

The fat lady hasn't sang yet on this engine. The engine runs, you have seen that in the videos. There is still 10" of snow in my yard, and the temperatures are still below freezing here in the daytime. When the weather warms up enough that I can get this engine off the corner of my desk and out into the main garage, with the big garage doors open, I will be able to do a lot more playing with the hit and miss action without the potential of gassing myself.----Brian

 

[Keith140]

Hi I am progressing well with my farm boy but would like some advise, how much of the oring on the piston should be proud of the piston? I have made the grove 110 tho deep but have about 1/3 of the o ring showing proud. I have also made the piston a very good sliding fit regards to all Keith

 

[Brian Rupnow]

Keith--Measure the cross sectional diameter of your o-ring.--They are always different than what they are listed at. Cut the piston groove so that 0.010" of ring sticks above the piston surface. The rings I use are listed as 1/16" O-rings, but they actually measure 0.070" in cross section. I cut my piston groove 0.060" deep.---Brian

 

[Keith140]

Many thanks Brian , I constantly refur to your fantastic thread and have lost count of the times of have read it, no doubt I will be back here again! Regards keith

 

[Brian Rupnow]

Today I finally got around to taking this engine out to my main garage where I could run it for as long as I wanted with the garage doors open. I haven't been happy with this engine. It seemed to me that driving two sets of gears (one set of helical for the camshaft and one set of bevel gears on the governor) made it simply too stiff to coast any amount of time when in miss mode. When I build an engine in the dead of winter, I can only run it on the corner of my desk in my design office, and I'm always afraid that I might gas myself with carbon monoxide. Consequently, the gears and bushing surfaces never get a chance to totally "wear in" and eliminate any "friction points". I've had it running now without the "governor lever" on it for about an hour and it hasn't boiled the water in the cooling reservoir. The carburetor on it still seems very "fussy". There is an extremely small band between going so slow that it starves and stalls, or going so fast that it wants to disintegrate. I will keep you posted on any improvements that I make.

 

[Brian Rupnow]

After rebuilding the carburetor and installing a new Viton ring on the piston, the engine is running as good as it is ever going to. This is the final video of it running, and I'm quite pleased with it. I do sell the plans for $25 Canadian funds.---Brian Rupnow

 

[JohnBDownunder]

Looks good and sounds a really good hit and miss engine.
As usual another great watch.
Thanks for the journey Brian.
Regards,
John B

 

[Brian Rupnow]

I'm terribly bored today, and as a result of having cataract surgery on both eyes (I've had one done, waiting another week before they do the other) I can't see well enough to read, or design, or machine something. And those are damned near all that I do. I have this sideshaft hit and miss engine set up in my main garage, and it starts so easily and runs so well that I now have about 10 hours run time on it. I just took a vide of it running today, because I can at least see well enough to do that.

 

[Ghosty]

Brian, It takes a lot of skill to machine a crankshaft like that.

 

[JohnBDownunder]

Always a joy to watch your engines run Brian. Hit n Miss are my favourite regardless of maker.
Must come from being a boy when these things were in general use. Shows perhaps, that I too am an old codger of 78 orbits around the sun.