Four stroke three cylinder radial of my own design

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cooksservices

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Hey guys, here is my latest engine. I have been working on it for a little over two months in between buying a house and family duties. I promised my self that I would stretch this one out and enjoy the build a little more but once I get going I spend every spare minute in the workshop. My first two engines were built using only my myford ml7 but taking delivery of a Bridgeport mill this allowed me to be a bit more adventurous with this project and a great one to learn milling operations. It’s amazing how nice it is to use a real mill after doing so much milling with the lathe!


This engine is a 27cc crankcase induction three cylinder four stroke radial engine.

It has three separate gear driven camshafts at the rear of the engine.

The ignition is taken care of by three sets of contact breaker points opened and closed by eccentric cams on the rear end of the cam shafts.

I have no plans for this engine as i built it with total freedom as I went along. Some pars were governed simply by what sizes of material I already had in my minimal stock pile.

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Great work sir!
It takes a lot to go off the deep end, design, & build your own engine & make it run.

Great job, keep them coming!

John
 
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Ohh no!! It seems my video has been banned as the radio was playing in the back ground I don’t have the rights to play that music! I’ll get another video up ASAP
 
Very impressive and unique. Cant wait to hear it running.

What influenced the design of the piston? It has a profiles dome crown & what appears to be wider ring groove. Just curious.
 

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I think WMB is Warner media group. I have shortened the video to remove the radio from the background hopefully this will be ok. If not I’ll make another video. Rest assured that that I have now made a nice throttle linkage so that I don’t have to reach behind the prop to rev up the engine ☺️. I just designed the pistons so hat they look nice the dome doesn’t really serve a purpose as the engine has a large squish. The pistons are around 4mm from the cylinder head at tdc. I didn’t want this engine to have too much compression. The large ring groove is for the viton o rings that I have used for piston rings. I do feel this is somewhat cheating but is s nice way to prove an engine design. I could make some cast liners and new pistons with cast rings at a later date.

I have over 400 pictures of machining operations if any one would like to see how anything specific was made.

Thanks for looking :).

 
Looks very good and sounds even better, how much running time will those "O" rings provide ?
 
Congratulations ! Great engine, great sound.
I have over 400 pictures of machining operations if any one would like to see how anything specific was made.
I and many people really want to see how it was made
Please !
 
I’m not sure how long the o ring piston rings will last but the ring groove is designed not to put too much pressure on the cylinder wall and let the compression push the o rings out. This way they are only really wearing mostly on the compression and ignition stroke. I have read a few articles on here about using viton o rings as piston rings and this is where I took my information from. It seems to work well, the engine has now run just over 750ml of standard pump fuel with 60/1 two stroke mix and it doesn’t have too much friction and seems to bounce well on compression.

Is there anything in particular that you would like to see? As I have so many photos I’m not sure how many I can post on here.

Thanks for all the great comments guys
 
Wonderful. Love the sound. Beautiful engine.
Mike
 
If you have a Dropbox account you could load all of the pictures to that and then post a link for people to view the folder, just a suggestion.

xpylonracer
 
I LIKE it. I don't have the knowledge to design an engine and you impressed the heck out of me.
 
Is there anything in particular that you would like to see? As I have so many photos I’m not sure how many I can post on here.
On the forum : Each department has some images that you like
If you want more, Google drive is a suggestion
Again, Great engine !
 
Love the sound of your engine Cooksservices - your workmanship looks great. I can already imagine it in a scale Lysander doing low my slow passes down the runway!
Like others have said; I’d love a copy of the drawings, but I believe you said you didn’t make any and built it using the stock you had available. That’s a shame but, as much as I’d love to see the plans, if I’m honest with myself about my abilities I’d probably not be able to make one and get it to run
Would love to see any/all the pictures you have taken - especially your set ups (really important to a beginner like me).
Thanks for posting. Nick
 
Cooksservices, if you don't have plans, I think with pictures plus measurements of key bits (and of how they assemble) one could make reasonably accurate reverse-engineered plans. Am I volunteering? Well ... let's say I'm strongly tempted. I know there are others here who could do a better job, but ... maybe ...
 

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