A stud welder is a cold wire welder like a mig. this allows you to position the stud apply pressure then turn on the current . An internal timer turns off the current returning the welder to cold wire condition. You are supposed to hold the gun still untill the puddle sets. The weld is a very high power short duration weld . Think of your 3/8 stud as a short 3/8 welding rod. (375-450 amps) The control electronics for studwelding is complex and expenive. Some have a bypass switch on them to allow hot wire for stick work. To me this is not a good feature as you are using a very expensive power source were wa much simpler and cheaper one would do. The biggest stud welder I have worked on was a Nelson dual output (two gun) machine welding 7/8 studs During the weld it was a full load for a 150 kw generator. Tthe actual duty cycle was above 28 % in use. this figure was computed from fuel consumption for the genset. For comparison a large sitck welder source is well under 30 kw when rumnning flat out. Terry
Last edited by terry lingle; 01-22-2005 at 09:13 AM.