What ever happened to MAPP gas?

[johansen]

I never had a chance to use a torch capable of melting steel with original mapp gas alone, but i can tell you it would be cheaper in the long run to just buy an oxy propane torch to get the same results.

My guess is the disappearance of mapp gas was just simple economics.

Also i dont know the numbers for mapp but oxy acetylene can reach 21.6 kilowatts per square centimeter heat flux, oxypropane is 5.6. mapp is probably in the middle.

So if you need to weld copper together, you are probably not going to have much luck with oxypropane. Going to need 400 amps of TIG or acetylene.

Ive gotten rather good with oxy propane cutting torches. From cold steel 1/4” thick to making a cut at the edge of a plate without preheating in as little as 10 to 20 seconds. Reducing flame for the start is better because the steel doesnt oxidise, and rust is a thermal insulator.

[soldar]

After doing research and watching videos, TIG welding appeals to me. Especially since I use aluminium quite a lot and being able to weld thin aluminium would be a big plus. For steel, I can resort to stick welding just fine (done that once and I'm quite pleased with the result). Today I looked at MIG welding aluminium as jpanhalt brought it up ( thanks, learned something new today) but the disadvantage is that MIG welding aluminium seems to be the start of the weld gets ugly and when progressing, you need to go faster. The creator of the video said that MIG welding aluminium isn't easy and he'd use his TIG machine if he wasn't (t)asked to make a video to show MIG welding aluminium.

I have only ever done stick welding, never TIG, but seeing videos TIG looks like quite a bit better in many ways. The problem I see is that it requires gas and once you get into gases you are paying to rent the bottles and it can get expensive even if you are not doing any welding.

I have often thought that many expensive tools require frequent use to make sense to purchase. I would love to own a metal lathe and other tools but I would use them very infrequently so it just does not make sense to buy them. I wish there was some kind of club or communal workshop where I could go and pay to use their installations.

Gas bottles to me are one of the things I try to avoid because they are expensive and inconvenient.

Stick welding only has one thing in its favor: it is simple and cheap. Other than that it is not as clean or as delicate as TIG.

[jpanhalt]

When I was doing it, MIG with aluminum filler needed a spool-on-gun.  I visited a shop that did truck body modifications.  They used aluminum diamond plate and MIG exclusively.  I thought the welds looked pretty good start to finish.

Besides working with very thin materials, if you flush the back side of the weld with shielding gas (I use argon exclusively), you can get a through weld where the back looks as good as the front. It takes time and for me good hearing.  The sizzle changes tone.  You can also see a change in the puddle with steel.  I have not tried that with aluminum sheet.

I use a variable foot control rather than something on the torch.  TIG also makes great welds on thermocouple probes.  For structural, like 8mm steel, you really need the amperage.    That's where I use MIG, unless it's just for fixturing.