Thread: Should i remove the blue paint before MIG welding?

I'm no expert but I've done a fair bit of welding (stick) and have never removed the blue paint before welding as it just burns off in the process. The welds have always been nice and strong.

It doesn't matter whether I remove the blue or not - my welds alway look ordinary but none have failed

Have never removed the primer paint when welding RHS in my 25 yrs of welding, I only clean RHS if it's had other paints, powder coating applied, as some of these can give off toxic fumes when welded.

You don't HAVE to remove it, it will normally burn off quite happily with a mig. Does occasionally make it a bit difficult to get the weld started, but once going it's normally fine.

I do usually remove it though, I find it makes the stuff just a little nicer to weld (plus the arc starts as soon as the wire hits). I'm also just in the habit of cleaning weld areas reasonably thoroughly since most of my welding these days is with a TIG, which tends to be pretty fussy about anything other than clean metal in the pool.

If you were doing a welding cert, I suspect you'd probably fail if you didn't remove the blue, but in terms of actual effect, I don't believe the strength of the weld to be compromised very much - the metal next to the weld will still normally fail first, if a failure should occur.

If memory serves me I think the blue paint is designed to be MIG friendly.

It's not any old paint, it's part of a coating system designed for easy fabrication and sufficient protection until properly painted.

Cheers

Justin

Yeah I agree with everyone, the stuff seems to be MIG friendly and probably no problems for general fabrication. Always nicer to weld clean metal though, just depends on how much time you have to play with it, or whether a spec demands the removal.

I have a little CIG Transmig 400 that I run .9mm wire in - never had a problem burning through the blue paint. But if it is Gal - then grind it back first or it will splatter a until it reaches the heat needed to burn the gal off - Gal also stinks - probably not good to breathe in either.

the blue undercoat on australian made rhs is designed to be weld friendly,however the paint on imported rhs is very often not as well behaved

Thanks everyone for your feedback.

Originally Posted by Jarh73

If memory serves me I think the blue paint is designed to be MIG friendly.

It's not any old paint, it's part of a coating system designed for easy fabrication and sufficient protection until properly painted.

Cheers

Justin

This is my understanding too

Dean