Clanford Clan 0.24-cc "Diesel"

[rklopp]

Here are a couple of photos of the "Clanford Clan" I built to plans published by Ron Chernich on ModelEngineNews.org. It runs, albeit SLOWLY. I think this is mainly because the piston fit is still quite tight. I deviated from the plans by substituting ANSI UN threads, some imperial dimensions for SI, making the conrod a little narrower, and whittling the venturi/tank top out of solid Delrin acetal. It starts with finger flipping, no spring starter required, as some web postings would suggest. The running is almost totally insensitive to needle position, so I may re-engineer that. The bore is 6.5 mm, stroke is 7.5 mm and displacement is 0.24 cc, or 0.015 in^3. Next on the agenda is a couple of 0.1-cc "Nano" "Diesels." Even though their displacement is less than half that of the Clan, the bore and stroke are both 5 mm, so not that much smaller than Clan's. I built Clan on comparatively beastly machinery: Monarch 10EE lathe (and Colchester Chipmaster for driving the bore lap), Deckel FP2NC and Aciera F4 mills. I used a 4X magnifier a lot.

 

[ShedBoy]

Nice job, any run videos kicking about.
Brock

 

[rklopp]

I didn't take a run video yet. I'll try to take one this week or next weekend.

 

[rklopp]

Nice job, any run videos kicking about.
Brock

Here's one without sound.

https://picasaweb.google.com/lh/photo/A9dJyHO-ttQswn_Qzczm79MTjNZETYmyPJy0liipFm0?feat=directlink

 

[steamer]

Nice build rklopp!

Dave

 

[GailInNM]

rklopp,
Very nice build.

I like compression ignition engines, but they sure can be a challenge. I have looked at the Clanford Clan a couple of times and even the Nano but I don't see me building either of them any more. I have built several CI engines in the 0.5 to 0.8 cc range. None of them were big balls of fire, but they did run successfully. I had a Allbon Bambi about 1960. It was 0.15 cc. Never flew it, but it was a lot of fun running on a "round the pole" prop driven race car in the garage.

Gail in NM

 

[rklopp]

Doh! I broke the crankpin. The engine had been running fine, and starting surprisingly easy, on a 5.5 x 3 prop, but that prop is too big. I decided to put on a 4 x 2.4 from an old Cox .020. The littler prop doesn't have enough inertia to allow finger starting the engine, so I grabbed the electric starter. Big mistake! The engine flooded, and I broke the crankpin.

The plans called for a separate pressed-in crankpin, but when I build the engine I turned the pin all one piece with the crank. Now I suppose I'll drill out the stub of the broken pin and ream for a separate dowel, just like the original plans.

 

[tomol409]

If the engine starts and runs at all, it will not have too tight a piston It sounds as if the engine is running rich. Test the needle valve by removing tank and blowing through the feed pipe. The needle should close up completely, then progressively open in about one and a half turns. If the needle is blunt it will be very sensitive. The engine would not start at all if the mixture was too weak - too little open.

 

[rklopp]

I made a new conrod and got it running again. It starts fairly easily by finger flicking. I put a slightly smaller prop on it, and it runs faster than before, but not enough to pull a plane. When I want a power trip, I can fire up my Mills 1.3. That thing really packs some grunt. I am working on a set of three 0.1-CC Nanos, so I'm not likely to try to squeeze more out of the Clan, especially given that Clans have a reputation for less than stellar performance. In other words, the fault may not be all mine.

 

[rklopp]

I built this Clan in late 2011, but could not get it to run well, because the needle valve was way too coarse, both in threads (2-56) and tip angle. I built a more conventional needle valve assembly with much finer threads (1-72) and a fine wire needle. That was a bit of watch building. Now the engine runs nicely. The video shows it turning a 5 x 3

[ame="http://youtu.be/UGJhh1as2E8"]http://youtu.be/UGJhh1as2E8[/ame]