Monsterman--HBF

My Feedback: (28)

Hi guys,

I have quite a few 5+ year old Cox control line planes I think they were all purchased from Toys R Us back when ya could buy them there.. I also have a few free flight helicopters. Anyhow I figured the other day I would try to get them running but I cant seem to find any "Cox" fuel cans or fuel anywhere on line.. Is there an airplane fuel that is the same or close enough to the Cox fuel to run in these??


Thanks
Chris

Mr Cox

The most important thing is to have only castor oil and plenty of it, i.e. about 25%.

"Modern" fuels tend to have synthetic oils and that will not work, neither for the ball joint or the liners. There are some commercial fuels that are for breaking in engines and these can have a high contents of castor but usually one needs to add a bit of extra castor even on those (sorry I don't know any brand in US).

Second most important thing is to not be shy with the nitro content, helps starting, handling and power.
I've ended up mixing my own fuel, much simpler than trying to find a commercial one and you can easily try a few different blends...

digital_trucker

Add an ounce of Sig Castor to Sig 1/2A fuel and you've got a winning combination.

Monsterman--HBF

My Feedback: (28)

Great so I just need to order some of this http://www.sigmfg.com/cgi-bin/dpsmar...001.html?E+Sig

& this http://www3.towerhobbies.com/cgi-bin...?&I=LXEPD2&P=0

And mix as stated above right??


Thanks again guys
Chris

skaliwag

My Feedback: (1)

If you are getting castor from SIG why not use their1/2A fuel?

http://www.sigmfg.com/cgi-bin/dpsmar...001.html?E+Sig

flyinrog

My Feedback: (1)

I get the fuel at the closest decent hobby store its Byrons 1/2a 25% nitro fuel, then I get benol from tower and just fill the pint bottle to the top,,works out pretty good so far....Rog

digital_trucker

IMO, for good fuel in a Cox engine (ball joint and all that) the Sig 1/2A fuel could do with a small does of castor...about another ounce per quart. For everything else that's small it seems to work absolutely fine, because everything else made within the last half-century uses a wrist pin.

Yes, I know there are exceptions, but they're few.

EX Model Engines

Interesting, where do you buy your supplies to make this? I ask because it seems I am always adding something to make the fuel right, so why not make the whole thing from scratch.

Mr Cox

I've found a LHS that actually have this in stock, and I'm happy to support them!

gcb

Chris,

I think the original standard Cox fuel was 15% nitro, 18% castor oil. Their Racing fuel had 25% nitro.

You can run with less nitro but needle adjustment suffers a bit.

Castor is for the ball socket as someone mentioned. Having some synthetic will prevent "varnishing", which used to be quite a problem. Also, the more nitro you use, the more often you will have to reset the ball socket.

Some RC fuels have as low as 14% lube. These fuels are formulated for large BB engines. That's why guys add extra castor. Also, some fuels have extra ingredients, mostly needed in larger engines.

I would suggest 15%-25% nitro, and 20%-22% lube, at least half castor.

Most fuels will work. Castor will protect better, especially at high temps (lean run).

George