What Epoxy Primers & Copper Weld Through for my Car?

[Retro Rust]

I'm getting a bit bogged down in what primers and rust protection I need for my Capri project. I've currently just got some cheap Halfords weld through grey primer but I guess I need something better for inside Sills or sealed areas (behind the spring hangers maybe).

1) For weld through should I be looking at a Copper weld through? Something like U-POL 2 Copper seems easy enough to get? I guess I could spray this inside the Sill panels or any box sections I'll never see again? I heard Copper is better than Zinc due to its melting point?

Pardon our interruption...

2) For a primer to spray on panels and repair patches should I go with an Epoxy Primer such as PROXL 1K Epoxy Primer

https://www.amazon.co.uk/ProXL-Epoxy-Primer-Aerosol-500ml/dp/B07Z5HKGR9?source=ps-sl-shoppingads-lpcontext&ref_=fplfs&smid=AUVABMVPKIPOE&th=1

3) I was also told to buy Por15 ? I know its probably not as good but could I get away with the Hamerite Krust? I'm guessing i'd only use either of these where it was still pitted and not being welded?

These examples are easy to get hold of from Amazon which is why I picked them. Also I know this has been covered in places but I'm just getting bogged down.

Thanks!!

 

[ajlelectronics]

I'm getting a bit bogged down in what primers and rust protection I need for my Capri project. I've currently just got some cheap Halfords weld through grey primer but I guess I need something better for inside Sills or sealed areas (behind the spring hangers maybe).

That's fine for temporary protection as it will wipe off.

1) For weld through should I be looking at a Copper weld through? Something like U-POL 2 Copper seems easy enough to get? I guess I could spray this inside the Sill panels or any box sections I'll never see again? I heard Copper is better than Zinc due to its melting point?

Weld through primer is useful stuff, but again it is temporary.

2) For a primer to spray on panels and repair patches should I go with an Epoxy Primer such as PROXL 1K Epoxy Primer

No because it is junk.

3) I was also told to buy Por15 ? I know its probably not as good but could I get away with the Hamerite Krust? I'm guessing i'd only use either of these where it was still pitted and not being welded?

20 years ago yes. Today definitely not as it is just the wrong medium for the job.

Today you should be using proper epoxy primer and there are a number of good ones on the market. For me it comes down to what you want to use it for. If spraying, then Lechler 29107 is the one to choose. It is an automotive grade primer which can leave a nice finish, so perfectly suited to bodywork as well as undersides.

If you want to brush it on and desire a thicker film in areas out of view, then Jotun products are the ones to go for. Not really suitable for bodywork or spraying, but excellent for undersides and anywhere out of sight.

 

[Retro Rust]

Cheers mate. Can you get these in aerosols ? Just having a look and i'm guessing they're for spray guns with compressors which I dont have. Will keep looking. I could do with something sooner rather than later. I guess the Halfords stuff will do temporary as you say.

 

[steveo3002]

^ can get 2k epoxy in rattle cans or brush it on hidden areas

 

[norsa]

My best advice for welding and primers is wire brush the weld immediately whilst still red hot then at the end of the session brush with epoxy primer. Welded in new box sections, apply masking tape to the cleaned weld surface, epoxy the rest and weld it in. Weld thru primers, for puddle welds, whilst not a bad idea are not a guarantee and still leave a burned residue behind which can attract rust if you can't access to wire brush and paint post weld. Nick.