What grit to sand fresh paint with....gezzzz

[bandit67]

Guys, was shooting some single stage solid color, white, and got a bunch of runs. Im sure it was operator error but second time using this new gun, don't like it at all. Any way, I have sanded out runs before on clear coats and used 400 and up , then buffed out. But have never had to sand fresh paint for a total reshoot. Should I use a coarser grit to start and finish with 400? Paint is about 3 days old now, thanks.

 

[68Moparmaniac]

800 wet/dry paper

 

[AR67GTX]

I would not finish with anything coarser than 600 but that’s kind of left over from the lacquer days. With urethane I think I would finish with 800.

Ah, 68Moparman beat me to it.

 

[zyzzyx]

You had better use a block and 360 grit to get the runs down to the rest of the paint level, and then use a D.A. with
600 or 800 to scuff the rest of the car. A D.A. will leave high spots that you'll be able to see later!

 

[R413]

Yes use a block or a nib to get the run off and get it flat with the surrounding area. If you just sand over it until it’s smooth you will create waves in the panel. The run will remain a high spot on the panel

 

[eldubb440]

get rid of the runs COMPLETELY....... or you will always see them to a point........

 

[eldubb440]

if you put a thin layer of finishing filler over the runs it will protect the surrounding area as the run gets cut..... sounds silly, I know it's a good bail out for small **** ups

but don't be afraid to open up the area and rework/reprime / reprep.......... every disaster is unique

me? I'd just cut to the chase....... eliminate the mess quickly and completely; right down to the foundation

 

[Rebelrouser]

Guys, was shooting some single stage solid color, white, and got a bunch of runs. Im sure it was operator error but second time using this new gun, don't like it at all. Any way, I have sanded out runs before on clear coats and used 400 and up , then buffed out. But have never had to sand fresh paint for a total reshoot. Should I use a coarser grit to start and finish with 400? Paint is about 3 days old now, thanks.

You would be faster to use a nib file to take off the runs. Then sand the paint for a recoat. I would use 600 and wet sand. Not a body man but have painted a few cars. And my biggest problem is I get a run every now and then. I don't know on single stage, but on fresh clearcoat and nib file will let you cut off the run and lightly sand then buff. Every time I try and sand a run with a block it takes off too much material on the sides of the run, and I wind up having to paint again. I have had a good old time body man show me the same technique with a razor blade.

Amazon product ASIN B08JH9LMM7

 

[eldubb440]

if you have curtains, there ain't no bailing that out....... you can improve the situation, to a point, with a lot of tedious work,

 

[69L48Z27]

I did good digging clear coat run out with 400 dry on a small piece of a plastic spreader. You can see what you’re doing vs wet. Trim the spreader piece to fit the run, like a finger. Apply pressure to a very targeted area. Once it’s all down start with finer grit and polish. Yes, tedious for sure.

 

[bandit67]

Did not know there was such a thing as a nib file, will get one. I did the taped end razor blade and cut the nib down best I could and hit it with some 320. Got some paint rolling but did not clog the 320 so I went wet sanding then and that began cutting pretty good. I cut down to the high build primer real good in the run area and then blocked up with 400, 500 and 600, the finest I had. Did it all wet and it looked good when it dried. I reshot using my primer gun, one of those from the 3 M disposable cup kits. I got a 1.4 head and reshot and was pleased with the out come. My old Sharpe gun I used for years crapped out finally and I went with a Finex model . It dumps a LOT of paint as it seems I move to slow to fit this gun.
As usual you learn much by fixing screwups and this was a first like this for me today. Most of what I have done was with 2 stage, and this single stage seems much more difficult for my limited experience. Once again, you guys were spot on, thanks

 

[AR67GTX]

Nib files work well, I think Eastwood used to sell them. One thing I've found when trying to eliminate a run or similar defect is to use a hard, flat block for flattening and blocking down - unless on a concave surface and then I use a large wood dowel rod. Blocks of hard, solid oak wood work well as they are hard, stable, typically hold a flat surface, are inexpensive and tolerate water well.