Paint Prep / cleaning dirt

[m3ss1na]

Figured I’d post this in here since there is no body work or paint category…

I have a few different questions but kind of all built into 1. Here it goes:

I’m painting my ecoonline. First thing is first-clean. Some spots have dirt so embedded, I can’t even get it out with a clay bar unless I spend 10-15 minutes on each 2’x1’ section (that’s a lot of time). Why?- because I have to go over with the clay bar at least 3 times before it somewhat smoothes out enough for me to be able to glide the clay bar. Then I have to press with all of my power on each square inch of this thing. It’s a lot of work.
*My question is, will wet sanding be a good alternative? It takes off the dirt beautifully and I’m sanding to paint it anyway (not going to bare metal) but, I’ve heard stories that when you sand before cleaning, the dirt gets imbedded into the paint and you can’t see it / clean it and it will cause fisheyes… I’m worried about that, so that’s why I’m using a clay bar to go around before sanding but I’m just looking for another way. I also don’t know what grit sand paper would cause the dirt imbedding that they were talking about (if I use 1200, dirt comes right off)…
Also, what about polishing? Could I polish instead of clay bar ? Or will dirt get imbedded into the surface and be a problem when I paint??

I’m trying to understand how dirt would get imbedded if you’re sanding since (as far as I know), it doesn’t make any enclosed/trapped areas that dirt can get stuck in (that I know of). Maybe microscopically it does. But, I’m trying to think how and I don’t understand.

Thanks, sorry for long explanation and sorry if it’s confusing lol.

Summary:

Should I clay, wet sand with 1200, polish, or just go straight to sanding with 220 to prep for paint?

P.S. there is A LOT of particles, not just dirt here and there. It’s Hundreds of particles per square inch.

I also might have missed things. Sorry if I did, I rushed this writing.

 

[dwcopple]

220 or 320

 

[m3ss1na]

Thx.
Do you have any input on the imbedding dirt if sanded? Seems everyone says to wash before sanding to get rid of wax, grease, & dirt. Otherwise, could cause catastrophic paint damage. I’m trying to find out why sanding dirt would be catastrophic damage. Or if they’re only referring to the greases and wax but I doubt it.

Like I said, a few people said dirt gets imbedded into the paint when sanded but I’m trying to find out why, and even if that’s true. Looking for an explanation here…

But I do appreciate your input

 

[m3ss1na]

Actually I was just thinking about it now after talking about it with someone. I assume the dirt is PRESSED into the paint by the sanding block, and not actually ‘lost’ in the “scratches”.
This would make a whole lot of more sense. I wonder if I just answered my own question again… lol happens a lot

 

[Fabulous50s]

Heck I've prepped good paint areas with scotchBrite and not had any troubles with fish eyes etc.

I'd think a coarser paper would do better at allowing contamination to fall off rather than get worked in.