There is a new specification available from AWS that deals with "qualifying" weldable primer paints.
The gist of the qualification test is:
Weld a T-joint that is painted with the “test” paint primer.
Weld one side with a fillet weld.
Weld the opposite side of the joint with another fillet weld.
Remove the first fillet by grinding, carbon arc gouging, etc.
Perform a fillet break test on the second weld that was deposited.
Evaluate the second weld for defects.
It is pretty evident that the first weld is going to blister and burn off a good amount of the paint present on the second side before the second weld is deposited. I have a difficult time imagining this test proves much of anything other than to give the paint manufacturers and the shipyards a method to hoodwink their customers and the American public into believing these paints are actually “weldable primers.”
I am forced to ask myself if ANY paint would fail this test? My gut reaction is that anyone that takes the time to read this specification will recognize this document for what it is.
As if our lungs do not already have to withstand the onslaught of fumes that include heavy metals, oxides, and who knows what else. Did this committee completely forget that one goal of AWS is to preserve the health of the welders that have to do the work? Maybe our savior will be OSHA and their requirement that the coating not produce objectionable, hazardous, or noxious fumes! Surely, I as a welder can no longer turn to AWS for guidence in preserving my well being. I cannot believe I am about to say, “Please, please OSHA save me from the idiots that wrote this standard!”
Just to be clear on this, I reread and revised my post several times and thought to myself that maybe I am being a tad too critical. My conclusions were always the same; the specification is what it is and there is no way to wash the brown stains out. They can slap a red cover on front and back, but it is still crap in between, period. I can only tell people to wear latex gloves when reading it. I can only hope none of the other AWS committees developing welding standards and codes adopt it. No matter how many times I've revised my post in an attempt to mellow my characterization of the new specification, I cannot do it.
This is just my humble opinion of my world as I perceive it.
Best regards - Al
By DaveBoyer 
Date 08-07-2010 18:27
Edited 08-09-2010 02:45
I guess it is like Dad always said "If it sounds too good to be true, It probably is"
I can understand a manufacturer wanting to protect parts against rust while in storage.
I can understand them wanting to save time and not have to remove the paint before welding.
I can understand a company trying to make paint that fills this need.
I CAN'T understand AWS making up a ******** qualification endorsing such a product if it really doesn't work.
If this product can be made to work if applied properly, the standard needs to be directed at the application process.
I sure was tired when I typed this, full of spelling errors, and I probably haven't fixed them all.
I started doing some reading lastnight about these primers and all I can say is thank guy I use a 3M repirator that filters out all the toxic cr*p. I have to buy these myself because the worthless company I work for doesn't want to spend the money instead they buy a $0.19 cents each crappy charcole mask for there welders to wear which leak.
Thanks everyone for replying. The balistic steel I weld on is for to save our troops lives and I'm scared for there lives everytime I weld on this so called weldable primer if my welds are good or not. I just do the best I possibly can with cleaning this crap but I dought it is really helping that much.
I keep thinking there has got to be other places to work that care more about quality then speed.
Too many mils of the stuff, is probably your biggest obstacle. Therfore grinding it off is the only real solution.
