I found that out too, not to use a grinder on aluminum if your going to weld it. It seems even with a grinding or cut off wheel made for aluminum it still embeds particles in the aluminum and the MIG does not like that. After learning that, I now always cut aluminum with a shear or saw, no problems there. Plasma cutter if I have to. Sandblasting also cleans good but again embeds particles in the aluminum.
Fun4now, I use the little SS wire brushes with the wood handles, cheap and work pretty well. I have a cup one too but I usually us it for cleaning up when done.
Some good info welder_one
Fun4now, I use the little SS wire brushes with the wood handles, cheap and work pretty well. I have a cup one too but I usually us it for cleaning up when done.
Some good info welder_one

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