How much sanding

[username0048]

How much sanding can i get away with on the gelcoat? I'm down to 320 and it's not removing the shadows from the old decals...

The first photo is after hitting it with 500. The 2nd is after 5 minutes or so of 320. The streaking is water where I tried to dry it.

And I saw harbor freight has sanding disks for a DA. Is that too much? I'm afraid of trying the DA and burning through the gelcoat.

 

[burtshaver2021]

Are you wet sanding? I wouldn’t use a DA and I wouldn’t go any courser than 320. The gelcoat is pretty thick but I wouldn’t use only do it by hand. The ghosting is still pretty prominent considering you went at it with 500 and then 320, I’ve never went courser than 400 grit and won’t ever use the 400 again, way to much work for me to sand out the marks the 400 left.
I wouldn’t use the 320 for another 5 minutes or so in that area and then move up to 600 grit no matter what the results.

 

[burtshaver2021]

Use a dab of car soap in the water and a sanding block. I used some hard foam I had as a block