Blow torch to re-activate clear coat?

[bradleyheathhays]

Thanks for the link. Just got their shipment in yesterday...1 can of primer, 2 cans of color and 1 can of 2k clear. They didn't offer tinted or high build primer like I was hoping so I ended up getting what they call their Aerosol Primer.


I started sanding at 320 and after seeing the deeper divots were too hard to smooth out I switched to 220 and gave them all a solid once over. 2+ hrs of hard rubbing and ended up red from head to toe. I spent some time smoothing out some of the easier divots that were on corners but didn't have the strength to get into any more than that.


As I go forward with sanding up through these grits do I need to stay where I'm at now at 220 and smooth out all the remaining chunk outs before moving up? Or will the (non high build) primer end up filling those and smooth out with sanding?

 

[tjmotter]

you should be ok with starting to move up. You could probably pick up a high build primer from your local autoparts store. While it is best to stick with one brand when aiming for a chemical bond, this layer is almost all physical bond so brand consistency is less important. Here is an example:


https://www.oreillyauto.com/detail/...otive-car-2006-audi-a4-quattro?q=primer&pos=4

 

[bradleyheathhays]

Well, here's where I've got to...

I sanded everything up to 600, filled the dings with putty, sanded back up to 600 then coated with 2 dashes of high-build primer. Next step is to wet sand with 800 then go to color and clear coat. Question is...how do I go about sanding the curved parts? Basically, each piece has 6 curved plane surfaces to sand...

1 is 1/2 to 1 1/2" wide
2 & 3 are both about 2"

4 is 1/8" wide
5 & 6 are 1/2" wide

This might be illustrated better by my original pictures but surfaces 1 and 2 are flat enough they could probably be block sanded, but 3 is mostly an all bulbous curved surface. 5 and 6 are probably flat enough to be block sanded, and 4 is so thin I won't be doing anything there but knocking off the edge between it and 5. Don't want to risk getting too close to 3 and scratch it with the edge of the paper. It's thin enough I don't think remaining unsanded will matter that much, but let me know if I'm wrong here.

2 questions are...

How do I go about sanding that curved 3 surface?

Before coating with primer, my previous sanding got down to the plastic in a few places. If I sand through the primer (to plastic or paint) and wet sand up to 800, will the paint layer stick to that? Or do I need to re-coat with primer if I sand through?

 

[Runnin'OnEmpty]

I use a flat sponge to block sand
curved surfaces like that. If you burn
through, give the spot a light shot
of primer, then lightly sand it.

Looks like your prep is going well...

 

[bradleyheathhays]

It took both coats of primer to get everything looking that solid grey, so I'm betting any kind of flat sanding is gonna burn spots on that curved 3 surface. My biggest goal here is just to color correct these things and not make them look perfect. Ideally I'd like them to blend with the rest of the body, which is v nice actually but has a thump here and there. So perfection is not something I'm striving for here.


And with that in mind, I'm thinking I could play it safe and just finger sand the whole thing using just a single layer of sandpaper. There's an element at play here I haven't explained before, and it's a rarely heard phrase. But it's, 'done's better than good.' Basically I'm in a hurry so getting them done and back on figures in here too.


Thanks for the positive feedback. No surprises so far.

 

[RCP Phx]

Your getting a lesson on why painting a car is so expensive and time consuming if you want a good job done!

 

[bradleyheathhays]

I did a whole car's body work correcting/filling and paint job a while ago just to get the skill set down, so luckily I've been through this before. And I swore I'd never do it again because of all prep work it takes to do it right. But this one isn't so big of a job really, and I'd be afraid to guess what it'd cost to have someone else do it.