Mig welding tip #8
Be sure to match your contact tube, gun liner, and drive rolls to the wire size you are using.
Using .030 drive rollers with .035 flux core innershield can really just piss you off and make you want to quit welding.
Flux core wire is hollow. It is made by extruding a metal sheath around finely granulated flux. So imagine squeezing .035 hollow wire full of flux thru an .030 gap.
The wire is going to get pinched and mashed and is not going to feed or weld good. The flux even gets mashed around making the wire burn erratic. Or what about using .035 drive rollers with .030 wire? You might find yourself changing the wire feed speed all the time and never getting it right, when the problem is just slippage of the wire on a groove that is too big to get traction.
You can get away with a few harmless things like using a .035 tip for .030 wire... but for a lot of other things, you better not screw with them! They will just drive you crazy!
You are better off matching everything so when something goes wrong you don’t have to chase down 10 different possibilities.
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