baz67
09-29-2004, 08:52 PM
After fighting contaminated welds while gitting in the other minitub it dawned on me I must not be cleaning the metal enough. So what are some ways all of you guys prep the metal before welding?
Brian
Matt@RFR
09-29-2004, 09:14 PM
For mild steel with a MIG, make sure it has no undercoating on it. Wipe off any grease with acetone/MEK/laquer thinner, etc, then grind to shiny silver metal. That's as clean as it ever needs to be. The shiny silver part is, in reality, optional as long as there's no rust. Also make sure that where you attach your ground is as clean as what you're going to weld. Allways.
If you still get porosity, you have gas coverage problems.