The reason that you don't see the gasoline system in use is that it is incrediably dangerous. Imagine a tank of gasoline in a welding area. Not a pretty thought. The lack of popularity has nothing to do with who own the aceyylene companies, it has to do with common sense and safety.

The 'latest' gas is called Mapgas. It is a mixture of acetylene and natural gas. It burns hotter than acetylene but requires slightly more oxy to operate and takes a bit longer to heat up. It also requires a different style tip on your tourches. The barrel and cutting attachment remain the same. We use it exclusively where I work. It is noticeably cheaper than acet. and safer. Mapgas does not spontaniously explode as will acet. at over 15 psi.

If you are working mostly with relatively thin metal, say under 1/4" or non-ferous metals, then plasma is the way to go. It is clean, doesn't distort the metal like oxy/acet., and is a lot cheaper to operate. Reasonable rigs can be had for about $1,200. They often show up in pawn shops where you can bargin them down to $800. The draw back is that they do require a small compressor.

For welding thin metal mig is the way to go. TIG is very handy if you work with non-ferous metals, esp. aluminum, but on an average day you would rarely use TIG.

I imagine you're right about the gasoline cutter. My teacher said where they are really good is for emergency work in the field cause you can haul a lot more cutting power on your back. I don't know the specifics but it makes sense -- 2 gallons of liquid gasoline would probably have the BTUs of a much heavier and larger acetylene tank.

Also, with the portable applications, you don't have the problem of having gasoline stored in a welding shop.

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Te futueo et caballum tuum

1986 300SDL, 362K
1984 300D, 138K

cmac,

The 'amount' of heat available doesn't really matter since all you need is enough to get steel hot enought quick enough to oxydize in the presence of oxygen. If you are trying to weld 2 railroad rails together that is another matter. For that you really need a lot of heat, in which case you use Thermite welding.

I don't mean to sound overly cautious about safety but I am over 60 years old and have been working with cutting and welding for about 50 of those years and in heavy industry for about the last 35. I would say 'luckily' I still have all my fingers,toes and eyes but in reality luck has nothing to do with it. I am always very conscience of safety around my work place and I must say that having a couple of gallons of gasoline in and around where I am using vast quantites of heat and oxygen would rate right up there on my safety meter as something that I might want to avoid.

Thermite is some crazy stuff. I've heard of people grinding steel, then grinding alumn. and having it randomly explode on them - thats scary...

MAPP is what we use here, Instead of propane (it's over doube the price, though)

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-1983 VW Rabbit LS Diesel (5speed, VNT/Giles build)

i do belive i posted a thread on Fun With Thermite..

Well, I'm not trying to sell the damn things. My teacher was pretty savvy and he thought they had some excellent uses. He said emergency personnel were using them because they were lighter and more compact. They could haul them on their back up a ladder much easier and with more staying power than a similar acet. unit.

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Te futueo et caballum tuum

1986 300SDL, 362K
1984 300D, 138K