Weld Through Primer?

I use the SEM copper weld with great results. The arc strikes nicely through it but as stated above the shelf life is not that long. Only buy what you will use in 6 months or so.

I have a HUGE welding job on my 1958 rambler super, "the big car" (series 10), and have wondered how I was supposed to cover  the weld with primer and paint, when the other side of what I welded wasn't accessible anymore... (there's places in the front of the cars floor areas that are boxed, the floor your feet sit on are separated from the underside of the car by a hollow area, this has made it hard for me to primer and paint the welds on the interior of this area) I was just doing my best and using tremclad spray paint and noticed the paint was destroyed by the MIG heat, but didn't know what else to do, ubtill I saw this thread and learned about this wled through primer, I've done about twenty hours or more of welding the drivers side floor area already and it's basicly done, but am starting to think I should zip cut it all out and do it again using this paint to do my best to stop rust from happening.... Or I could start using the weld through primer now but leave what I've done for a few years.... The rust should be not advanced enough to cause a structural concern at that point.

So even though it's not the primer, it still was a good product to use before welding? I bought some, but saw it wasn't primer and wondered if I should return it and find the same product but the primer....but if you didn't use the primer and all's well.... Also, I had a experience yesterday with a troublesome spray can of clear coat I was using, my valve cover was rusting and a simple sanding and priming job turned into a very extensive sanding job followed by a clear coat, when I was using the spray can of clear coat, it clogged after the first coat was almost finished, it was a huge pita moment, I was so pissed off. I phoned the store, and asked them if there's any tricks I could do to fix the problem, they said take off the tiny button you press with your finger and soak it in some acetone, I asked if 99%iso alcohol would work they said yes, so I did that, and they also said to soak the can in hot water, I got a pot of water steaming on the stove, it was hot enough I couldn't keep my hand in the water, but I wasn't going to be injured. After a few minutes I put the tiny cap back on the can and tried using it again and it was working fine, not just fine but very well and the product sprayed out very effiently, I suppose because the hot water heated up the contents and made it want to come out of the can faster, and the finger button was cleaned out real well with the alcohol.... So, if any of y'all have greif with spray cans in the future, that's a tip for you guys, it sure helped me and I was able to finish my job. 

Edited by 1958 rambler super - Feb/24/2022 at 11:01am

 When I am done using spray cans I always clear them out upside down for a few seconds then I wash out the nozzle and top of the spray can with brake cleaner after that I air blow them clean especially Rust-Olem cans that can be sprayed any angle it makes a difference. 

Edited by JGRANTAMX - Feb/25/2022 at 5:14pm

When I fire up the welder I have, I turn the wire speed all the way down and turn on the gas and the regulator and all that and I pull the trigger until the sound of what's coming out of the gun changes, letting me know there's gas right there for when I start the welding, then I turn up the wire speed back to which ever I was using it. I was also looking at that Eastwood product and wondered how easy it would be to make one of those spray hoses they sell.