Temperature at tip of a neutral flame on an oxy-acetylene torch is almost 6000 degrees F-- critical temperature of mild steels (1018 AISI) is aprox. 2350 degrees F-- use of Mapp gas instead of acetylene is aprox. 5300 F-- propane 5120 F-- not all that many welders today know how to recognize a neutral flame-- in part due to: Usage of plasma arc to cut and pierce ferrous metals- usage of the right oxygen pressure and delivery of fuel gas is critical to a good solder or braze joint-- In soldering, you do NOT break down the parent metal of the joint being soldered, in brazing you approach the threshold of bringing the parent metal to its critical temperature-- The key to both processes involves moving the flame cone constantly--
Two criteria I have when I visit a welding shop, especially if they have TIG-- (1) available supply of TemilSticks-- (2) separate smaller wheel grinder for Tungsten only-- RWTF member AWS--
