Originally Posted by
unterhausen
Propane-air or Mapp-air makes it really, really hard to be successful. I know I couldn't build a frame with those gasses. A good torch, an oxygen concentrator, and a gas grill propane tank is going to set someone back $600, but they actually are going to work. And they can easily be re-sold. But otherwise, a diligent person can do a lot with meticulous prep, a file, a vise and a reasonably flat surface.
I had a copy of Talbot 40 years ago until someone "borrowed" it and never gave it back. I wonder how many frames he ever built (eta: Talbot, I'm sure the book thief never built any). I don't think my copy recommended propane, that's a pretty good sign of a charlatan as far as I'm concerned.
Most of my frames were built with MAPP-air. It worked fine, and in some ways was easier than oxy-acetyline, because of the big, soft flame. You have to be patient, but it's hard to overheat the joint, and it's hard to concentrate too much heat into too small an area. Now, MAPP-air for
brass brazing is tough, but the OP wrote that he's using silver.