I have give this some thought for several years now and finally made up my mine to make my own 55 CC engine. So far I have the front case half about finished. I still need to radius a few places. The rest of the material is on order for the back half. Since I don't have a CNC milling machine there are just some things that is not feasible to do with a conventional mill W/O making some very elaborate setups, so I decided to keep it somewhat simple. I'll post pics as things progress. I used a DL-50 for the mule but I will be making several changes to things.
I may go with the 55 DL cylinder and piston, not sure yet. Since one of the changes is the crankshaft I will make my own crankshaft & rod.

Nice. Keep the pics coming.

congrats on this outstanding project, look forward to updates

matt

COOL

Hey Cyberwolf
Excellent work

But from one engine maker to another - a big warning.

It is very very addictive.

When you hear that first one start up, it is as good as life gets, the culmination of the dream.

Then comes the

"Now if I change this, then, - - - - "

Followed by the

"Now I wonder if I can make a - - - - - "

and before you know it - it is your newest passion.

Don't ask me how I know this -

Good luck on the venture and feel free to pm me if you have any questions on things - or even just to mull ideas over. .

thats great!!! good luck and let us see more pics.

Nice project. I'm with Aussiesteve on this one. Don't fall into the what-if trap.

For starters I would like to thank everyone for there kind words and encouragement on this little project.
I was able to get the crankshaft material here locally , I opted to go with 4140. A little different cutting than that tough old Aluminum *L* but still better than Stainless or some of the other materials I have run into. Anyway with any luck I should have the mill work done tomorrow, then its wait for the rest of my materials to arrive. After talking with Aussie Steve he comfirmed what I had in mind. The crank will be a 2 piece I have not made the pin yet, I may rough it out and finish it after I have the rod bearings in hand and the rod made. anyway heres a few pics hope you like them.

beautiful work!!!

Yeah nice !!! I'll be watching.

Hi guys ,here is the finished product,It actually looks to have come out so the rod will be on the centerline of the cylinder, Woo Hoo" I did sumpin right.

I would like to hit on something I know we all have went thru at some time or another, you buy a new engine and it has some problems, sometimes major ones sometimes minor. Untill I starterd this deal I really never took a long hard look at what went into one of these simple little engines, Believe me there is alot more than what meets the eye at first glance. I have spent several days just doing the math and blue prints in this project and there seems to always be something that comes up to make me change my line of thinking, either not enough material or something. And I had something to look at and compare I can only imagine what it would be like to make one W/O anything just a thought in ones head.
So next time you have a problem just remember what all has gone into one of these before you get really frustrated. I know some of the R&D is not as good as others are, but there is still alot even in the lesser grades of engines. The end result is something that will run for years and be mainly trouble free, at least thats my way of thinking. anyway I just thought I would share a little bit of what really goes into one of these little things. Hope you enjoy the pics, more to come as soon as I get them.

Keep it up and everyone will want you to make them one. [X(]

I got my material today so its back to work in the AM
I have run into a slight problem maybe some of you can help, the bearing I choose for the big end on the rod is available according to the catalogs but I need to buy a half a truck load just to get one, anybody have any thought on where a person may get this type of bearings. So far I have checked with Boca,timkin,fafnir and of couse a few dealers, no luck so far. Thanks for any help here.

I can't help with the bearing other than suggest dropping a line to RCIgn. He's got a line on most everything.

On another note, if you elect to try your hand at another 55, try using the 3w 55 cylinder. Pricey, but it has the best porting available for the engine type. Big gains could be had by many manufacturers if they went with port designs later than 1970.

WOLF

LOOKING GOOD,BUT I WOULD OFFER SOME ADVICE ON THE CRANK. YOU NEED TO STRESS RELIEVE IT. I AM WORKING ON CONVERTING DA 50'S TO DA 60'S WITH A STROKER CRANK AND DL JUG AND PISTON. MY FIRST CRANK BROKE AFTER ABOUT 10 -12 RUNS BUT IT HAD NOT BEEN STRESS RELIEVED. MY OTHER CRANKS HAVE NOW BEEN DRAWN BACK TO 28 RC. YOU NEED TO HEAT THEM TO 600 DEG FOR ABOUT AN HOUR.

GOOD LUCK
DUANE

Thanks for the suggestion TOM,I may just do that very thing next time around. Aussie Steeve was right when he said there addictive, so far I have had a ball making this
I went to a 3-W site and looked at the porting and its quite different than what I have seen in other engines, Off subject, I just sold a NIB 3-W 275-CS I got in trade to a fellow up in Montanna. Of course I didn't take it apart,but if the insides looks anything like the outside does It had to be a winner of a engine. I just didn't have anything large enough airframe to justify keeping it. Way to rich for my blood so to speak *L*
Anyway I got started on the back half of the Crankcase (sorry no pics yet) but I should be able to get that finished up tomorrow depending on how I feel.
I also contacted a engineer friend of mine I do work for and explained my delema on the bearing issues, He was good enough to do some looking and thought it shouldn't be a problem getting me just one or two bearings, I hope he is right.
Next time around I will have the bearings in hand and build to fit them ,not depend on the bearing book only to find out you have to buy several to get just one. hope everyone is doing good and flying as much as possible.

Thanks for the info. Relieving the stress in the crankshaft has crossed my mind several times. Since I don't have access to an industrial oven anymore I'll have to look around and see what I can come up with.

Finally got back to the case, still needs a few things polished up but so far so good. If things will leave me alone for a while I can have this ready to go I hope, already have my next project in mind. Believe me it will be alot different than this one is.
Here is a few pics of the progress. Sorry the glare from the alum is kind of bright and makes the pics a little fuzzy.

Lookin good! shotpeening can be used to stress relieve to if unfinished,good luck!

Wow, this is great and I'm impressed and a bit jealous. I always wanted to make my own engine, but I can never seem to get the time to get started on it. Also, I need to buy another mill...

I've just got too many projects going. Maybe when I get my present "batch" of projects done, I can contemplate something like this. Meanwhile...

Keep going, good luck, and keep us posted!!

AV8TOR

I looked around here locally and found a guy that had a furnace, I now have a purdy ultra violet crankshaft*L* Next time around I will use a different material and won't have to stress relieve it. I knew about the shot peen method of stress relieving we used it all the time on Aircraft struts and what not, they would strip the chrome plating off then shot peen and rechrome and then we would regrind back to size.
I plan on raising the compression on this engine, fairly simple to do if I made my own jug, but since I am not I can lower the squish area but doing so will change the port timing a little bit and I need to do more checking into this before I start cutting up a cylinder.

I finally was able to stay somewhat on track with the engine parts, Heres a couple of pics from my last endeavor.
Again I choose 4140 material for these 2 items, then heat treated both to a Rockwell of 55 C, Just the rod ends not the center part. It may not be quite as hard as needed but for this go around it will have to do. Also if anyone is wondering why I didn't cut the center down more I'm waiting on the final assy to see where i'm at for balance.
Since I am still waiting for my other parts to get in, I now have some time to plan out just what I want to do with the compression issue. I may just go the stock cylinder to start with then do some mods and see where that goes. Mapping out the ports is a little time consuming but it will let me know if there's any improvemts that can be made. I do know one thing, I will clean the ports up if nothing else. I'll have more as soon as things progress, again thanks to all for the encouragement on this.

Heres a few more pics of the progress , the one pic is the hub holder I made for the DL-50 55 engine's I went with 3 bolts instead of the two, maybe a over kill but whats one more hole when your set up. I placed a cylinder on it so you folks can get a idea of what the finished product is going to look like the first go around. I still need to cut the key slot in the crank and add the magnet to the hub, drill the 2 holes for the hall sensor, but I have had enough for the day *L* I'll get back on it in the AM. Hope you enjoy the pics and please feel free to make comments.

This is great project for the advanced model engine enthusiast, I commend your efforts and applaud your craftsmanship. However you may want to consider deciding which cylinder to go with now, 50cc or 55cc, they are not the same. The stub on the 55 is 2mm larger and the bolt pattern is different enough it won't work if drilled for the 50cc.

Keep up the good work!