What causes Burn Back?

admin

What causes my wire to burn back into the tip when I go to start a weld?  Too much heat, speed, or too much wire sticking out, wrong tip???  It's an older Miller 250  with 75/25 gas .035 wire.  It seems to be doing it more lately I used to get along time out of the tips, now I can have a pile laying on the ground at the end of the day.  Thanks for the education.  TB
Reply:Could be many different things. Is your contact tip clean ?  When I use .035 wire I put in an .045 tip, it gives you a little more clearance for the wire and is less apt to "clog". Are you keeping your whip straight? Sometimes the wire will have a hard time traveling thru the whip if it is rolled or kinked. Do you have a good liner in your whip? They do get contaminsted (clogged) with dust or debris. Also check your guide tubes that feed the wire thru to your feed rollers at your wire frre they will get clogged too.  One last item, I have purchaced wire that seemed to have kinks in it, it makes it almost impossible to feed right.  good luck and happy burnin
Reply:Not enough gas? Not enough wire speed? Both of those happened to me and willl seem to cause burn back.
Reply:also drive roller pressure to lose but you don't want them to tight either
Reply:generally too much voltage per wire speedIF it Catches...Let it Burn