Originally Posted by Boogie_
3M Putty Cote
Very smooth and creamy, easy sanding.
Any auto body paint supply will have it, or a similar knock-off brand.
I will apply it with a razor blade on a small pit or scratch.
Don't pile it on, there should be little to no putty on the panel surface, just fill the scratch.
Several thin passes allowing the putty to cure with light clean up sanding in between coats if needed.
If the scratches you're working with are contained under the new vinyl decals, 180#-220# grit sandpaper is the finest (as well as the roughest) you'll need to use.
180 and 220 is way to course to use on the gelcoat that is on Fibron Sheeting. Since the OP unfortunately used a metal scraper he has scratches in the gel coat. The only thing that will fill and last on gel coat is gel coat. Yes. You can put putty in it, but with time it will fail.
The proper way is to get some gel coat from a boat supply. It is two part mix. Sand around the gouge with 1200 or finer wet or dry sandpaper with a flat sponge sanding block. At the gouge, turn the block on edge just a little to open the gouge up and bevel it just a bit. Apply a light goat of gel coat into the gouge, allowing it to cure. Again wet sand with 1200 paper. Do this two or three times until the surface is flat and smooth. You should not have any gel coat more than 1/4 inch wider that the gouge. And you while you will lightly sand outside the gouge, the concentration should be to get the gouge level with the surrounding surface.
Then go from 1200, to 1800 to 2400 sandpaper, working your way out from the repaired area. Since this is going under decals an exact color match is not needed. But I have fixed deep gouges in boats for years this way. The toughest was getting the color match exact, so a 1 inch wide gouge from a boat dock was invisible. Done correctly, all the new material is in the damage, and none over the undamaged area. After 2400 sanding a light buffing is all that is needed. I have spent hours tinting gel coat to get an exact match. On a camper with decals you just need to be close enough ti does not show through.