ckangaroo70

My Feedback: (51)

You are correct. While I note that I mix in 100 ounces...using metrics where everything works in 10's is the same principal.

Johnkpap

This spread sheet may help a few people, it can be found at.

http://www.gmac.org.au/fuelcalc/index.htm

Arty's fuel is a great thing saves me alot of time.

Johnkpap

buckfarkl

I just read an article from the internet ( http://www.scootworks.com/rdrc/fuel.html ) and this guy had some interesting things to say about mixing oil and nitro and methanol. I think its worth a look at if your wanting to do your own fuel.
In one part he said that you don't need as much oil as we previously thought. Most manufacturers say 15% oil but this guy says wedon't need to add that much.
I'm going to try a batch for myself( just methanol and castor oil. 10% castor and the rest methanol and see how my engine performs.
I've read some of the other home brewers that have done their own fuels for years at 16% and had no problem what so ever. I think maybe 16% is over kill.
Read this article and you'll see that the manufacture wants to cover their behind. More oil in their mind is better for warranty purposes.

Moderator opened up the URL so it would be a live link

downunder

While generally that's quite a good article there's one part that I totally disagree with (OK, that's a polite way of saying he's wrong ).
"Too much oil - any more than is necessary - makes the engine run really crappy. Think about it: methanol burns; oil doesn’t - or at least it shouldn’t. (Some do, but that will be dealt with in another installment.) Common sense would tell us that the less oil (nonburnable) we can safely use (to an irreducible minimum point, of course), the more methanol (burnable) we will have in our combustion chamber. More burnable ingredients = more power."

It's wrong because the needle valve is set to regulate only the flow of methanol/nitro regardless of how much oil is in the mix. Adding (or reducing) the amount of oil in the mix just means you have to readjust the needle to regain the original correct flow of methanol/nitro. With the same flow of methanol/nitro the engine will produce the same power.

Also I'm not too sure how much oil is needed to make an engine run "really crappy" because on the test stand I use 25% all castor for every engine and they all run beautifully. Maybe 40% might be a bit much though .

ckangaroo70

My Feedback: (51)

That would be my understanding as well.
I can see no benefits at all to running an engine on low oil content fuel. I would always side on running a bit more oil than needed instead of less. Go out and drain the oil in your car and see how long it runs without it. Oil is the life life blood of any engine, and the Methanol and Nitro is the food and drink for energy. Some RC engines like those in RC cars and trucks get by with less oil because they are run in burst and not wide open throttle for 15 minutes straight depending upon the type of flying being. Thats why I would never run RC truck fuel in an airplane engine without adding extra oil, but I ran all my RC Monster Monster Trucks on Airplane fuel with higher oil content, and they all ran great on it and left nice smoke trails.

buckfarkl

i need to know if a guy can use 2 stoke synthetic motorcycle oil to mix with methanol for my airplanes?

ckangaroo70

My Feedback: (51)

I am not certain as to what oil you have, but only certain type oils are designed to be mixed with methanol. I use Klotz..which is designed to mix with either gas or methanol, but there are other brands also that are designed to mix with alky.

buckfarkl

I see that there is light,medium,and heavy castor in coolpower.what do you recommend as far as mixing up some home brew with methanol and one of these coolpower oils?I don't know if i should go light or heavy.
I was going to just get some castor oil but here in madison,wi. Ican't seem to find any. Help anybody.

jeffie8696

WalMart Pharmacy. Nice source if you are just mixing up a half gallon or so for testing or just adding a little extra to some fuel for a break in. Make certain it has no added sugar, it usually says so on the bottle.

downunder

I don't see how Coolpower can say that because castor is just castor. It's a bit like saying do you want light, medium or heavy water (and yeah yeah, I know there's such a thing as heavy water but you get the idea ). Motorbike or GoKart shops may have castor if the LHS can't order some from their fuel suppliers.

buckfarkl

I tried walgreens for castor and also walmart but they only cone in 6 oz size bottles.i guess i will just order some from online from some where.

Sport_Pilot

I believe that is the Coolpower made for alcohol powerd go carts. It can be used for model engines as well. It is a blend of castor oil and synthetic, the light, medium, and heavy reference is to how high the percentage of castor oil is to synthetic oil.

downunder

Now that makes more sense but do they say how much castor is in each blend?

jeffie8696

The pharmacy castor is a little expensive for full blown fuel mixing but is a quick and easy step to fortify a gallon of retail fuel or just mixing up a small quantity for testing or break in. Half A engines that don't burn very much fuel anyway can last quite a while on a quart.
That is how I mix it up, I just add enough to a small container of retail fuel to bring up the total oil content enough to keep my Cox engines happy. Retail half A fuel tends to be expensive(lot of nitro , lot of lube).