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Bit of an issue with a job, we have an artic full of box section that requires numerous plates welding on. As requested it has been shot blasted to SA2.5 and finished with a weldable primer.
On every other job where we have had steel finished this way, it has welded fine. This job..welds are full of porosity, ugly and spattery. A lot of times the wire won't arc through the paint. It certainly smells like weldable primer when it burns off. So far we have had to grind the paint off at every weld location which is a mare.
The data sheet for the water-based weldable primer seems to think that it should go on at 20 microns. It looks to be on a lot thicker than that, but i can't be sure.
I'm going to bat it back to our supplier but whats the likely cause? Thickness? Am i best doing a DFT test on it to get an idea. Its been applied on an automatic line if that makes any difference?
All advise greatly received.
On every other job where we have had steel finished this way, it has welded fine. This job..welds are full of porosity, ugly and spattery. A lot of times the wire won't arc through the paint. It certainly smells like weldable primer when it burns off. So far we have had to grind the paint off at every weld location which is a mare.
The data sheet for the water-based weldable primer seems to think that it should go on at 20 microns. It looks to be on a lot thicker than that, but i can't be sure.
I'm going to bat it back to our supplier but whats the likely cause? Thickness? Am i best doing a DFT test on it to get an idea. Its been applied on an automatic line if that makes any difference?
All advise greatly received.