Denatured Alcohol for fuel?

It depends upon the other compounds included in the gallon of ethanol. Without a statement verifying a low water content, I don't think I would bother trying to use it.

On the other hand, if you have a fueling station selling automotive ethanol, that might be worth a try. Our local station that sells E85 is fifteen miles away and it sells for less than 87 octane gasoline (10% ethanol). I'm planning on buying some when I get over that way with the appropriate fuel container. E100 would be more attractive, but the E85 (15% gasoline) would be worth a try. I don't think that we will have any problem burning E85 with a standard glow plug.

One fellow I know who is in the know said that you can mix Klotz Techniplate with E85 ethanol based motor fuel without having mixing problems. You still have to use as much oil as you would have to with methanol (17% to 25%).

Ed Cregger

There is a small ethanol plant opening up in the area. They built the plant when gasoline was over $4 per gallon so I doubt they are doing very well right now. Anyway they might be interested in selling me a small quantity of ethanol for trying out for model airplane fuel. If it worked out I wouldn't mind purchasing enough ethanol, oils, and nitromethane to supply model fuel for the local area, they might even be interested in getting into the model fuel business themselves since gasoline prices dropped.

I looked up info on the internet and there are suppliers for home fuel ethanol production. They have something they call a microsieve that takes water out of alcohol and is reusable. I thought if I could experiment with Wal-Mart denatured alcohol it would be worth a try to blend my own.

RogerN

Model airplane fuels use methanol. Denatured alcohol is only part methanol.

If I understand correctly, methanol is wood alcohol and denatured alcohol is grain alcohol, i.e. ethanol. I think from what I've read, they take drinkable ethanol and poison it to make it non-drinkable and sell it as denatured alcohol. The ethanol plant in the area told me they have to mix a certain percent gasoline in their alcohol, to make it not drinkable, before they sell it. Perhaps Methanol is used in model fuel because you can get it pure since it's not suitable for drinking.

If ethanol would work for model fuel, a person can get a legal still and get about 3 gallons of ethanol per bushel of corn. It comes out of the still about 96% IIRC and then run it through a microsieve to remove the remaining water. Anyway, there is a small ethanol plant about 20 miles or so from here. If ethanol would make good model fuel maybe they could sell me some pure if I added nitromethane and/or oil before they let me have it.

The reason for my question is that I have some 30% heli fuel with 22% oil content that I would like to cut to maybe 15% oil to use in model cars, if denatured alcohol would work.

RogerN

Methanol is the cleanest burning alcohol. Everything else leaves residue.

Why not just go to a drag racing store and buy some racing methanol? Then you won't have to worry about compatibility issues chemically.

I did buy a gallon of universal thinner at the hardware store once, which turned out to be mostly methanol, according to the label. I mixed it with a quart of castor oil and the engines started and ran just fine. This was back when flying control line, so there were no throttling issues to test.

Ed Cregger

Denatured alcohol is ethanol alcohol with a denaturing agent ( some sort of poison) added to make it unfit to drink. Still it's basically ethanol alcohol. The glow plug equipped engines that we all know and love require methanol. That's because the ignition of the fuel is caused by a reaction between the methanol and the platinum in the glow plug wire element. It is this reaction that causes the fuel to combust and the engine to run. Simply stated, the engine won't run on ethanol (denatured alcohol) because ethanol doesn't react with the platinum in the glow plug. It just won't work.

Thanks, that's what I was wanting to know. I knew there was something with the platinum in the glow plug that causes combustion but I didn't know if it worked with only methanol or also ethanol.

RogerN

I have run an engine on denatured alcohol- just briefly and by accident.

I was cleaning it and for some reason I attached a glow igniter- with barely a flip of the prop it started right up- just burning the alcohol in the carb and cylinder head- there was no fuel line connected.

Denatured alcohol has methanol in it.

I'm trying to find a drag racing store in the area to see if I can buy some methanol. I have found a place around 50 miles away, I e-mailed them to get a price on methanol and nitromethane. I can get oils online without the hazmat charge (I hope). Anyway I don't like paying $32 per gallon of 20% RC car fuel and I'd like to use up some of my heli fuel. I have a small flying area now and it's more suitable for my small electrics than the 60 glow fuel heli's.

Thanks for the info! RogerN

With the glow plug being heated by the igniter, the engine would probably run on a multitude of fuels. But to run _normally_, there needs to be methanol in the fuel, ethanol just ain't going to do it. As I understand it, the platinum acts as a catalyst causing the methanol to react with oxygen, i.e. burn.

I looked up denatured alcohol and found out one way they can denature/poison it is by mixing in methanol. There is a drag strip and a race track in the area, if I can find a methanol supply in the area then I'll be set. I just thought if I could use denatured alcohol then I already knew I could get it from Wal-Mart or the hardware store.

I thought I could buy a gallon of 30%, some klotz oil, and some methanol, and mix up 3 gallons of 10% or 2 gallons of 15%. If I can mix 3 gallons from $30 worth of fuel, $10 in oil, and less than $10 methanol, I can have 3 gallons of 10% for $50 without the hazmat fee. Actually I'm considering something more like buying 50% nitro and stretching it with Klotz and methanol.

RogerN

alcohol sold at hardware stores the same stuff you would

A glo plug will work just fine with ethanol. It will also work just fine with acetone or lots and lots of other light organics. That catalyst on the wire is NOT specific to methanol. In fact with acetone you do not even need a precious metal. A high temp copper alloy wire would be fully adequate. Something like monel for instance.

The reason glo engines use methanol as fuel is all engines run on heat. So the more BTUs of fuel air mix you can stuff into the cylinder per combustion cycle the more power you get out of the engine. It is simple high school chemistry to calculate if ethanol is as good as methanol and it is not. Nor is acetone. But your engine will run on either of them. You might have to change the compression ratio a little to get optimum performance from alternate fuels. The small amount of water in denatured ethanol is irrelevant. The only thing that matters is you must not have so much water in the fuel that it causes the oil to separate. If the oil stays in solution the water makes no meaningful difference. In fact tests on methanol based fuels show slightly increased performance with a few % of water in the fuel. Those test results were published in one of the model mags a few years ago.

So bottom line is if you do not mind giving up a little power lots of alternate fuels will work just fine. But every one of them will cost you power vs methanol.

Now, if you do not want to give up power you could experiment with real high nitro content ethanol. But the cost of the nitro will drive the fuel cost higher then methanol based fuel so why bother? You could also look at burning anhydrous hydrazine and get more power than methanol based fuels. Of course it is going to eat up your engine pretty fast. Still, you might get an hour or two out of it before it was totalled. Liquid ammonia is another possibility. Same corrosion problem and you also are dealing with a fuel tank under 40 or 50 psig. Acetylene would be another logical choice. Now you are dealing with a possible explosion if you do not know how to handle the stuff.

Bottom line is methanol is the best overall practical choice for max power output, ease of use, life of equipment and user safety. If there was a better choice the fuel manufacturers would be selling it.

Do you have any idea what the other 70% is? Take a guess. Hint: It doesn't burn.

-- Ray

My 30% Cool Power is supposed to be 30% nitro, 22% oil, and the rest methanol. I'm guessing you thought I meant a gallon of 30% methanol with

70% water? For my model car sport fuel I thought I might try 10% nitro, 16% oil (may be revised between now and then, some use 9% oil in racing), and the remainder methanol.

RogerN

Just wondering how "Choose your own blend" would work for clubs? A club could buy a drum of Methanol, a few gallons of Nitro, castor and synthetic oil. Out of that they could mix FAI, 10% sport fuel, heli fuel, high nitro, all synthetic, all castor, or mix synthetic and castor... all the popular mixes + club members could design their own custom mixes if they wanted. Club members could buy the fuel they liked the best or be able to buy the components to brew their own "secret" blends.

Just a thought, seems better than buying a drum of one kind of fuel to try to fit everybody.

RogerN

Yes, I was referring to alcohol versus fuel. The 90% alcohol you get at a drug store, when opened, immediately becomes 87% just from being opened to the air. The longer you leave it open, the faster the alcohol evaporates. Within hours, you will find yourself at the 56% point which is where it seems the surface tension of the water can and will keep most of the alcohol from evaporating. The 30% alcohol is often used on those pads that doctors use to wipe your arm before you get the needle. The mix is such that the alcohol will stay in solution a long time. But there's heaps of water in the mix.

I've been following this thread with interest. I wouldn't advise using alcohol in model two stroke engines. What happens inside the engine is that the water in suspension in the fuel can cause a rapid expansion inside the chamber and actually crack a head. When people leave their weed whacker outside and moisture gets into the two stroke gas mix, the same thing often happens. You must be very careful when you introduce water into your fuel mix. Try experimenting with an old but serviceable engine that starts easily. The first thing that you will notice is that starting is very, very hard when you add alcohol. That's due to the water in the fuel/air mix. Unavoidable.

-- Ray

It's been my experience that mixing your own, even with buddies involved to split up expenses is not cost effective when you factor in the mess and trouble. A 55 gal drum of menthol would require about 15 gallons of oil and about the same in nitro (in 5 gal buckets). Then you have the storing/moving the big drum around, mixing, minimizing exposure to air, getting 85 - 90 bottles, getting rid of the drums, etc, etc. Much better to buy as you need it and eat the extra bucks a gallon. In addition, most commercial fuels have other additives that don't normally get added in home brews.

If you are trying to dilute down a high nitro bottle of fuel, the easiest way is to buy a gallon(s) of FAI (0 percent nitro) or 5% and blend together as needed to get the reduction you want. Prolly would not have to bother with buying extra oil, bottles or mixing equipment.

Just a thought......

Tom

Easier than calculating is to burn it in an alcohol lamp. Methanol burns with a pure blue almost invisible flame. Denatured alcohol or anything else burns with yellow in the flame.