Mig - melting nozzles and dirty tips

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Hello, 6 months experience with my Hobart 190 and still working on consistency of my welds.  Most are good, but lately I've been getting melted spots in the tip of the nozzle.  I'm also getting black soot around the the tip (which I think is from nozzle gel, but seems to happen more often when I have the nozzle getting into problems).  Occasionally, the wire balls up and sticks to the nozzle or tip, requiring that I clip it off, sometimes having to replace the tip.  Maybe this is par for the course, but I'm on my second nozzle and have a couple small spots that are gone from burning away, etc..I'm guessing it's position.  I'm either getting too close, but in many cases with the needed 1/4" stickout, the nozzle has to be pretty close.  When I try to consciously pull back further, I feel like I'm feeding in lose rope and I break the arc.   Or maybe I'm getting too far over, but I don't notice it.  Most of the problems seem to occur on tight spaces like welding a fillet joint.  Any ideas on tips or things to do to correct?
Reply:slow down the wire feed, sounds like too much wire coming out of the tip....Of all the things I lost I miss my mind the most...I know just enough about everything to be dangerous......You cant cure stupid..only kill it...
Reply:Usually if the wire is arcing to the nozzle, the insulation in the nozzle has been bridged by crud, or the nozzle has touched the work,and is closer to the tip than the work.The wire sticking to the tip is usually from too slow of a wire speed, though it could also be from actually touching the work with the tip.
Reply:Occasionally, the wire balls up and sticks to the nozzle or tip.................balls up or looks like a birds nest??Of all the things I lost I miss my mind the most...I know just enough about everything to be dangerous......You cant cure stupid..only kill it...
Reply:I have on occasion bumped the wire feed and had it get to fast the wire hits the metal and arcs to the tip causing it to stick.Hope this helps Good luck
Reply:Originally Posted by roadkillbobbOccasionally, the wire balls up and sticks to the nozzle or tip.................balls up or looks like a birds nest??
Reply:What kind of wire and size are you using and what machine settings? There's several things that could cause it. Worn out tip, wrong size tip, wrong drive roll pressure, dirty liner, not enough shielding gas, etc., etc. The more info the better to help figure out the problem.
Reply:You should be able to weld with the nozzle dragging on the plate and not have the nozzle get damaged. Clean all the tip dip off you Miggun, make sure nothing has bridged the nozzle insulator. Then see what happens. If you must use dip. Weld a little first and get the gun hot.Dip only a 1/4 inch in. Let drip off. then go back to welding. Or better get a can of no stick spray.To much dip can block the nozzle and affect gas flow. Burning to the tip can be caused by worn out tips and bad liners. Might be best to tune up your miggun with a new liner, insulator , tip adapter (diffuser) and nozzle. exact consumables will depend on model of gun.How old is  your Hobart welder? wire and gas used, Nozzle set up, Flush, recessed, sticking out.Are the drive rolls the correct size for wire used or are they worn. Try pulling the wire by hand through them with gun removed. If you can pull wire through and drive rolls do not move you might have worn out drive rolls OR motor bearing. Should not be able to move drive roll up and down. High drive roll pressure will cause bearing to ware out. should be just tight enough for good feeding.
Reply:Do you have enough wire speed?  That may be the reason if you are getting burn back on your tips.
Reply:Originally Posted by Welder DaveWhat kind of wire and size are you using and what machine settings? There's several things that could cause it. Worn out tip, wrong size tip, wrong drive roll pressure, dirty liner, not enough shielding gas, etc., etc. The more info the better to help figure out the problem.
Reply:Originally Posted by ccawgcYou should be able to weld with the nozzle dragging on the plate and not have the nozzle get damaged. Clean all the tip dip off you Miggun, make sure nothing has bridged the nozzle insulator. Then see what happens. If you must use dip. Weld a little first and get the gun hot.Dip only a 1/4 inch in. Let drip off. then go back to welding. Or better get a can of no stick spray.To much dip can block the nozzle and affect gas flow. Burning to the tip can be caused by worn out tips and bad liners. Might be best to tune up your miggun with a new liner, insulator , tip adapter (diffuser) and nozzle. exact consumables will depend on model of gun.How old is  your Hobart welder? wire and gas used, Nozzle set up, Flush, recessed, sticking out.Are the drive rolls the correct size for wire used or are they worn. Try pulling the wire by hand through them with gun removed. If you can pull wire through and drive rolls do not move you might have worn out drive rolls OR motor bearing. Should not be able to move drive roll up and down. High drive roll pressure will cause bearing to ware out. should be just tight enough for good feeding.