Cheaper Oxy acetylene source?

It is possible to weld with MAPP gas and oxygen if you are very careful.

Possible, but certainly not easy and really only for small parts. The welds can easily become a bit porous / brittle if overheated. If you had a corner seam to weld, say in 16g steel, it would weld a treat, running straight down with minimum filler rod. But less easy welds become progressively more difficult.

Many years ago I did use it for much of the welding to restore a car, and it did a pretty decent job actually, with good solid welds, but I heard that the formula for MAPP gas changed for the worst (welding wise) a few years back, so I doubt I would rely on it for such a job now.

I mostly use it now for heating, which it's great for, and the odd bit of brazing - I use the stick or TIG welders more often for welding.

Cheers - Will

Hi Russell,

It's Propylene.

Nick.

Hello Tony,

I don't think you have that correct? "Profuel secondary flame burns twice as hot as acetylene". I believe it is actually about 200 degrees centigrade cooler.

Anyone that has used Profuel and acetylene, can they say what their experience was of the two? One person says they don't notice the difference. On the one occasion that I used it, I was underwhelmed. Maybe I had not got the correct nozzle size, I used the one that I would normally weld with acetylene, maybe there is some difference?

Andrew.

PS, there is a hobbyweld agent very close to me, I will go and chat with them.

Thanks. So, it's the same as the current formulation of MAPP gas.

Russell

Ah, I think i'm showing my inexperience there! Thanks for explaining it to me, yeah it does work exactly as you said, go to cherry red and the oxidizing flame starts to push the slag to one side, with plenty of sparks.

Michael W

Anyone claiming (as quoted above) that a temperature is twice as hot as something else needs to learn some basic physics.

Look at the three temperature scales in modern use - and take a figure such as 10 degrees. Twice as hot would be 20 degrees, you might imagine, but this gives quite different real temperatures in each case. Now try it with a below zero figure ... Twice as hot as -10 is, in F, C, K, respectively, verty cold, quite cold, and impossible.

Unless, of course, the text came from a politician or a marketing person, then you would know it was a load of testicles, of course.

Cheers, Tim

Hi Andrew

That's a cut and paste directly off their site

personally I don't notice any difference

tony

Acetylene; 1475 BTU per cu ft, temperature 3482*C. Oxygen to gas ratio 1:1

LPG; 2500 BTU per cu ft, temperature 2699*C. Oxygen to gas ratio 4.5:1

Ian S C

Hi Ian S C, I don't know where you get 3482 *C from, I've always known it to be 3100-3200. BOC says it is approximately 3150 when used with Oxygen **LINK**

It is still the only gas flame that can weld steel, properly.

Regards Nick.