weld through primer

[dian]

i have never used it, as it seems not to be available in switzerland.

i understand you coat the parts and can weld them together later? does it work with tig? how heat resistant is it? e.g. if i coat the inside of a 2mm pipe and weld it on the outside to a 4 mm plate (on the end), will it be destroyed?

[Tungsten dipper]

I would say anything welded by tig should be CLEAN. No paint, oil, scale and etc, should be shiny metal for the best results. This goes for all metals especially aluminum.

[nickel-city-fab]

Tungsten dipper is correct. The so-called "weld-through" primers are mostly intended for structural work with cellulose coated rods ("stick welding"). The primer burns off in the heat affected area and has to be re-applied over/after the weld.

[dian]

so neither tig nor mig? then i dont need it. (just bought some on ebay.)

[gzig5]

Weld through primer works fine with MIG. I have better results with the copper based products than the zinc based. You coat the mating faces and when the weld melts the primer, it converts into a rust resistant coating on the interface that you can no longer access. You still have to clean the rust and crap off the mating surfaces and then put a coat of the primer on each.