some fusion o/a gas welds with my opinion

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The first two welds are of fusion welds on 3/8" sq bar sandwiched between two 1/8"x1" flat bars.  The 3/8" sticks up about 1/16" above the two flat bars.  You can see a crest in the second photo.This picture is using a no4 tip.  MECO weldmaster torch and tip.  The o/a pressure.  oxygen pressure at about 30psi.  While it welds, the puddle doesn't spred out, it only wants to go forward.Same tip oxygen around 8.  The puddle spread.  The welding actually goes faster. Much more controllable puddle.  This stuff hypnotizes me.This photo is of a the completed panels.  I did both houses, 7 panels.  I had to copy a previous design.My opinion.  Lower recommended pressures give larger more controllable puddles.  With higher pressures I never get popping.  However, with lower pressures I do occasionally get a pop.  If a pop occurs I adjust the angle of the torch or pull it back.  If pop persist, then I increase the flow first.  If popping still persist then I will increase pressure slightly.  If popping is very frequent then pressure are too slow.  Don't confuse pressure with flow.  Pressure is adjust at the regulator.  The flow is adjusted at the torch with the valves.  High pressure from the tank caused high velocity at the tip regardless of the valve adjustment.  High velocity makes puddle control difficult.    From my understanding, single stage regulators (most common) pressure  will change as volume in the tank changes.  Thus,  pressure adjustments may need to be made as welding progresses.For newby welder.  An old o/a welding book will help much.  Northern Tool had a  really good book with nice color pictures describing all forms of welding.Last edited by tapwelder; 05-24-2008 at 02:42 AM.
Reply:Thanks. Very good explanation of what confuses many. It's tough to find many nowdays that truely know and understand oxy welding. I just love the second weld.
Reply:Cool, thanks for sharing.