I learned a lot about TIG brazing when I was modifying an oil pan for my race car.av8or1 wrote:Ok thanks. I haven't heard of many folk making claims later on in their ownership, at least not successfully. Concerning. I'll definitely need to give this more thought...
Speaking of thoughts...I've had one comparison that I've been assuming "must be" true, but it seems worthy of asking since I have little experience with TIG. So this TIG brazing thing ... it doesn't melt the base metal and introduces less heat than a normal TIG weld. That's to the good. How about a comparison to a MIG weld? I've concluded that the brazing would also be less heat input since the MIG weld will melt the base metal. Correct? And is the diff in heat input between a MIG brazing with SiBr wire versus a TIG brazing with SiBr filler rod/wire just a wash, ergo roughly equal?
Thanks!
Most important thing that I learned with regards to heat input: If you want to minimize the heat input, you have to use tiny silicon bronze filler rods. If the filler rod is too big, then it's counter-productive because you can't heat the filler rod directly or else it will ball-up on you. You need to heat the base metal and from there heat is transferred into the filler rod. Sometimes it actually helps to produce a tiny molten steel puddle to initiate the melting of the filler (kinda like how tinning a part when soldering helps the flow of solder into the joint), but a relatively small filler rod will likely be better overall.
As for MIG brazing vs TIG brazing, it all depends on the machine. Machines that can do pulse MIG can limit the heat input more than just running the wire "traditionally". I have a small roll of 030 silicon bronze for my MIG but I haven't had the time to test it out. I suspect that with the pulse program for it, it will greatly limit the heat input, just as pulse does with any other welding process.
Thats not in your sig 
