upol weld thru primer..bad welds

[steveo3002]

got some upol weld thru primer here , usualy i can do reasonble quality welds but with this stuff it was hard work and lots of brown residue

anyone else get the same?

 

[norsa]

It needs to be well dried and not put on too thick Steve but its not a patch on the Copper primer i used to use.
Nick

 

[Engineer1964]

With weld through primer i find this especially on structural steel work which comes in pre painted, that you do need to turn your welder up a fair bit as will as your gas, to be honest these are the gimmicks that i can do without and i do tend to sand or grind back to the bear metal to get a decent weld.

 

[norsa]

If anyone has a supplier of Metaflux copper weld thru primer I (and Steve) would be very pleased.

 

[maxrs]

just got a few cans from a place called metatec think there the only uk supplier of metaflux stuff

 

[langy]

I've never found weld thru primer to be very good to be honest, don't make sense really when you think about it

 

[justmental]

as langy has said not good as it burns away from the weld area so waste of time and money.

 

[Engineer1964]

Just weld first and prime after. Easy

 

[norsa]

Fair comments but it is supposed to form a barrier between the overlapped metals where you cant wire brush and prime. I have no reason to doubt it. I only use it on top jobs like the current Escort project but as previously stated, im old skool and set in my ways. Having said that however there is a school of thought that says if you try to set fire to a coating, it will form water between the coating and the steel where it tries to get as much O2 as possible????????

 

[langy]

Fair comments but it is supposed to form a barrier between the overlapped metals where you cant wire brush and prime. I have no reason to doubt it. I only use it on top jobs like the current Escort project but as previously stated, im old skool and set in my ways. Having said that however there is a school of thought that says if you try to set fire to a coating, it will form water between the coating and the steel where it tries to get as much O2 as possible????????

If your welding is any good it will be burnt away from the penetration, a definite no no with TIG too

 

[norsa]

Correct Steve but it is not designed for continuous weld, only for spot or puddle. Innit?

 

[langy]

Correct Steve but it is not designed for continuous weld, only for spot or puddle. Innit?

I don't know Nick as I don't use it but I just can't see it's only for spotting as surely if you wanted to continues weld you wouldn't be able too ???
If that makes sense

 

[keithski122]

Best stuff I've used was a wurth product, didn't cause problems with the weld unlike every other weld through primer I've tried.