Paint issue

[bil1024]

See the pics, not sure how this happened, I had to do a spot repair, and the base looks like it did something funky62171

[Taz Rules]

See the pics, not sure how this happened, I had to do a spot repair, and the base looks like it did something funky62171

Can't tell exactly from the pic... what exactly did the paint do?
From what it looks like to me, it almost looks like lack of adhesion. Did you use wax and grease remover prior to priming, prior to sanding (so you don't drive contaminants deeperinto the primer), and prior to paint? Or maybe some oil or condensation from the compressor made it past the filters and into your gun?

Tough to diagnose without seeing it in person.

[bil1024]

I sanded this portion and this is what I got, 62212

[Gordon Levy]

Shoot a pic in the daylight. The flash is messing up what we are trying to see.

[bil1024]

After little research, looks like the issue I have is call"mapping" going to try and sand down the spots and prime and respray base

[Taz Rules]

If the issue is mapping, sanding may actually make it worse, as what you are seeing with mapping is the several different layers of primer, filler, and fiberglass. All of these substrates sand at different rates, so blocking them will lower the softer layers (like filler) far more and far faster than the harder layers (like fiberglass). This will accentuate, not eliminate the problem.

If it is bad, what you may need to do is sand down to glass, or at least to glass and some filler (no primer in the opened up area), then re-do the filler over the whole surface, then sand that down.
As soon as you bust through the filler, even a little bit, stop. If you still have low and high spots, add more filler, then re-block again.
The idea is to get the filler built up, not the fiberglass ground down. You want a single component, filler only, exposed when you finish block sanding. (make sure the edges are feathered, of course).

I knock filler down with 100-120 grit (by hand with a block), then another block with 150, and then feather the edges and smooth the work with a softer block at 180 grit. DA the surrounding area with 180 for about 2-3" around the repair. First coat of primer goes over the repair and the 2-3" ring that you DA'd. 2nd coat of primer goes over the repaired area only, plus maybe 1" past, but MUST stay within the ring of your first coat. (The reason for this is because the "pebble" left at the edges is difficult to adhere to, and needs to be sanded off for a smooth finish anyway. If you go past your previous coats of primer, their pebbled edges will show up in the form of pinholes when you sand later) Be generous with the material. 3rd coat of primer goes over repaired area only as well, slightly smaller than the previous coat.

Allow primer to dry FULLY.
Now block with 240 (if the primer is rough or has runs), or 320 if its smooth. (If you did 240, go over it again with 320.)
If you bust through the primer to the filler, respray the primer. (If you bust through to the fiberglass, you have much, much more work to do and have skipped some steps that you need to go back and do.)

BTW, I should have mentioned...use GUIDE COAT for each stage of sanding.

Once you have the 320 done, DA with 400, then again with 600. Each stage of sanding should extend about 1/2" to 1" past the previous sanding radius. (think rings on a target)

If you are blending, hit your blend area (not the repair area) with 800 on a DA.

Degrease, mask and paint.

[bil1024]

Thanks Taz, appreciate your help, will try your method

[j.miller]

What you need to do is scuff area with 320, apply "water borne" 2 coats, wet sand 500-600 and apply base coat. Water borne is a great blocker for substrate problems. Make sure you let it flash between coats and let it dry completely . You want the temp 70 or above, you can use a heater to dry if its too cold...da bat

[Taz Rules]

What you need to do is scuff area with 320, apply "water borne" 2 coats, wet sand 500-600 and apply base coat. Water borne is a great blocker for substrate problems. Make sure you let it flash between coats and let it dry completely . You want the temp 70 or above, you can use a heater to dry if its too cold...da bat

I'm not familiar with that specific product. I assume its a sealer? Who makes it? I'd like to hear more, for sure...I'm always wanting to learn new techniques that can save time and labor.

Just an FYI to the OP, you want to be very careful mixing brand-names of paint products. They are generally designed by each company as a system to work together, and not all of the different companies' products are compatible. If you do decide to go the sealer route, get the same brand as the paint that you used, and follow the products TDS (technical data sheet). Some sealers are designed to be sprayed Wet On Wet (meaning just let it flash off, then spray topcoat). Sealers designed to be sprayed wet won't work once dry, and vice versa.

Not to say that there is anything wrong with the product mentioned above...I've just never heard of it, and obviously never used it before. It may work perfectly and be exactly what you want. God knows, my method is a pile more work! Just be aware that you need to follow the manufacturers' directions with any product.

Personally, if I was given the two methods listed above to choose from, I'd contact J.Miller directly and find out some more info about that product he mentioned. It seems like a ton less work, if your body is straight underneath and not actually wavy from the substrate issue. He's a Gold Sponsor and owns a custom shop....I'm pretty sure he wouldn't recommend something unless he is confident in it.

[j.miller]

The one I use from time to time is PPG EPW115. There are other brands as well. You are having a solvent reaction.....soo when you add more of anything with solvent the reaction gets fed. Water Borne has way fewer solvents to attack the area and once it's dry it doesn't react to solvent....hence a barrier coat.

[bil1024]

So tried resealing and repaint, no good. Its only where i try to blend into the current base / clear. Sanded with 1000 and get this, is the new clear not adhering to the old clear ? I used that melt away but no luck62475

[j.miller]

Give me a call. 951-676-0191...Jeff