[wayne gillis]

I would progress sanding from 80 to 120 to 220 to 320 , all the while ck'ing the tech sheet that came with the paint or primer products

[tech69]

yeah, I mentioned sanding it out at the source but most shops would do what you mentioned, including mine. It's sufficient. Just gotta make sure the primer is done shrinking. Bringing it back to at least primer and reguide coating it would at least tell you for sure it's sanded out, but not tell you if it's done shrinking. The trick would be the step ups in grit, but I wouldn't recommend 320 on a silver.

[cutthroatkid]

Let me explain this as best as I can in hopes you guys will set my but straight..I don't wanna go through this in the future.I the first time I painted the rig just scuffed with 400 then 500 over primer..it came out ok..since then I was using 80 grit&going right through the metal.Shot the high build primer I could see the scratch marks bad!Sanded it back down then primer etc..I just want the body to look as good as the paint I've been on this for 2 months..my paint is laying like glass.I've decided to take a full week&do nothing but prep allday.
So should I strip to bare metal?there's already a lot of spots where I hit metal.The main issues are where I removed the badges.The bed &grill,bumpers etc I left alone.So should I take it all down then go from 150 to 320 to 400&6-8 coats of 2 k high build primer?.Too be noted it was like as I was sanding the painted wasn't fully cleared&would look like hairs in the base...but main it laid like glass!Its nuts.
PLEASE help with how to fix these sanding scratches

[tech69]

are you saying the edges of the scratch marks of the original paint appeared to lift or look bloated? If so that's solvents reacting.

So are you saying it hasn't been cleared and is just in basecoat?
If so, go straight to 240-320-500. or 400-500-600. you can just 600 lightly and take little material off. Go to primer and guide coat once you hit it.

Please just give us the details.

Is it in base or clear?

[cutthroatkid]

Originally Posted by tech69

how was it feathering? Sometimes an old paint can make an 80 grit scratch appear to be a 40 grit scratch depending on adhesion of that paint. It could also be solvents reacting to the open scratches.At this point, it would be good to get some heat on it to shrink all that primer out. If it was summer it would be perfect to just sit it outside for a while and ensure that both sides get the sun.Then you can revisit it and have another look, but since it's silver it's most likely nothing you can do will help it other than dig back in it. If it wasn't bad and the color wasn't silver you might be able to get away with waiting for that primer to shrink then sand n buff. Probably not gonna work here. I'd hate to say dig in but if that's what you want to do that's what should be done. I'd go back with 80 on a block to primer and this time be mindful of going back over it with 180 to factory paint, and this time your 80 might not be as deep and your 180 scratches will be plenty out of fear, which is good and the right way. Just make sure you let things settle and cure before you sand then reprime and sand with 600, seal, and paint. you probably could get away with just going to the primer but those 80 scratches are still there so why risk it? If you chose to do that just guide coat it when it hits primer and I bet the scratches will sand out, but again, it's a risk if you don't take it that paint
where the problem is.

It feathered good in some spots others..bad.Right now the main problem is the scratches in the metal that the primer won't fill.

[tech69]

you can use 50-60 grit on a die grinder slowly and then 40 then 80 on a 3/8" throw DA sander. that should get it out. If that will mess too much up around it just throw a super tight coat and thin coat of filler over it and feather it out nice while leaving just enough to cover the marks.

[cutthroatkid]

Ok will do that I'm gonna slow down&take it nice& slow. how many coats of high build primer do you recommend?

[tech69]

no more than the tech sheet says, usually 2-3. The wetter and colder the longer the flash.

[deadbodyman]

You should sand your primer with 400 wet or 320 DA, nothing coarser...Primers take longer to cure when its cold out,when you can stick your fingernail in it without leaving a mark its ready to sand. This test works for paint too..

[cutthroatkid]

It was pretty warm in my shop it was dry to the touch in a matter of minutes..sorry if I seem obnoxious I just want this thint looking great now that does paint does...I'm gonna finish sanding down today then shoot with primer&let it sit over nite to see if it shrinks..does that sound good?

[tech69]

Originally Posted by cutthroatkid

It was pretty warm in my shop it was dry to the touch in a matter of minutes..sorry if I seem obnoxious I just want this thint looking great now that does paint does...I'm gonna finish sanding down today then shoot with primer&let it sit over nite to see if it shrinks..does that sound good?

in this weather maybe longer. The nail test as mentioned is good but even if it passes that you next gauge it on how it sands. If it starts to clog paper stop immediately. I personally like to at least kind of half arse go over any 400 grit scratches with 500-600 on a scuff pad to sort of buffer scratches out a bit when going silver, but that's just me. If I were at home I'd go to 500 then do the half arse sanding with 600 or may even wet sand with 400 then 600, reguide coating it, but that's merely cause I personally like how the metallic flakes look over a 600 scratch, but it's not a deal breaker. Just my opinion. I car and industry standard does say 600 over silver but it's not as important as they make it seem and what deadbodyman mentioned is good enough.I once worked with an old man who used 220 for everything and used 2k for a sealer...you bet them scratches came back on silver.

[cutthroatkid]

Originally Posted by deadbodyman

You should sand your primer with 400 wet or 320 DA, nothing coarser...Primers take longer to cure when its cold out,when you can stick your fingernail in it without leaving a mark its ready to sand. This test works for paint too..

Ill wetsand with 400 after I let it cure over nite

[cutthroatkid]

Since I can see the sanding marks on the primer do I sand all of the primer off or just build it back up

[tech69]

use guide coat and it will tell you whether they are sanded out. This is where curing good helps cause it may settle back into those earlier scratches at a later time.

[cutthroatkid]

First off I sent this to someone who is a great help with tips&pointers&greatest!Ill keep his name a secret but wanted to also ask on here not because he won't help cause I'm sure he wi just because you guys have been with me through all of this also..so here's a somewhat copy&paste...I just couldn't get the scratches to fill so I did something I thought would really take care of it
It didn't I hit the bad scratch spots in a glofball size shape&just shot tons of hi build primer till it looked like whipped topping.. It was the wrong thing to do..&after about a hour I tryd to sand it down&it made a pile of crap .I'm guessing it wasn't cured enough..well the problem with the scratch marks still showing ended up being because my cheap hf gun I've been using for primer wasn't cutting it.So I used my new gun(which I was trying not to use for primer) it fixed it all. With the 1.8 tip...can I wait overnite till these blotches I sprayed&I really laid it on can I sand em down&feather them then spot shoot where needed?
Bust my chops all you want I deserve it I'm new to this I have nobody but you guys&my email helper..but I will not lie when I screw up Ill admit when I do something wrong&I won't give up!I mean my paint really laid like glass no orange peel I'm taking extra time making sure I mix correctly&I'm not using cheap stuff any longer..I had 6 hf purple guns&there two 'pro' gun kit..I tool stripped down parts I may be able to use&through the guns In the trash&if anyone can recommend any good dvds on this type of work Ill buy em.
I can't think of any work more fulfilling then taking some old&making it look new.I know I'm a far way away but I've made up my mind this 100&a zillion % want to do this.Tomorrow I'm even gonna call some paint&body shops&ask if I can work
For free for month or two to learn.
Please just tell ke how to fix this screw up I have for the da 80 grit,150 220 320&400..for the block 500,1000,80,&400 HELP