Stainless Steel Mapp/Air torch?

"...And sometimes when the surface you are trying to braze will not tin for nothing or nobody, you have to get it hot /then/ scrub it down with more flux and a stainless wire brush. And all of a sudden it decides to clean up and wet with a vengeance. ..."
Thanks Bruce. you may be right about the surface. when it was hot enough to puddle the bronze, it didn't always want to stick.
Come to think of it, when I used that "brazing fuel" tossable bottle the tip(~1.25") of the SS tube got red hot. That doesn't happen when I use yellow MPS or MAPP tosstanks.
About the home sized bottles: I absolutely agree the disposables are a waste of time and money..... the next step up to the refillable(or swappable) 50cf tanks so I can use my harris rig is the logical choice. you figure the pair with fill should run about $250 USD? I was quoted $400, but thats here in the great white north. Still seems a bit steep even after taxes. I'll look further.
thx to all for all the input -mark

You were quoted full price for brand new and full, which probably isn't too far off. They do show up at garage sales for far less, and even if it's only half full you still can buy the tanks for less than the deposit value. When they run out, then you take it in for exchange.
But you do have to know to spot abused cylinders that are both dangerous to have around and worthless - dented, rusted, broken filler matrix inside the Acetylene bottle, Acetone fill missing, etc. Have your local gas supplier show you what to look for - it's basic safety knowledge you should have if you are going to use them.
Having a cylinder go Deflagration on you would tend to ruin your whole year - they just go BOOM!!! spontaneously.
If the older cylinder you turn in for a refill is out of Hydrotest (12 years) some suppliers charge extra to exchange them - but that's a profit center dodge, because they see no problem at all when they give one to you as 'refilled' with 11 years on it, and your last one turned in before that had a fresh hydro...
Honest shops average it out as a cost of doing business. Charge everyone an extra 25-cents a fill rolled into the flat fee, and let it average out to just test the cylinders when the date comes due.
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Why would you spend $400 for tanks for MAPP gas, when for that kind of money you could get a used OXY / Acetylene torch setup.

I didn't - I have two sets of B Acetylene and 50CF Oxygen. When one runs dry you have enough to finish the project at hand.
MAPP uses the same basic POL tanks as Propane, same fittings, etc. AFAICT you just change the labels.
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