Wet Sanding for deep scratches-
In the case I have some deep scratches- which most trailers do sooner or later, I know that I can make them disappear from view by wet sanding with the proper grit and procedure.
You have to be intelligent in your assessment of how deep and where to start in abrasion level to properly remove the scratch without causing more scratches than necessary.
Light scratches- I ALWAYS try a lighter grit than what I initially assume will work. If you have a light scratch, try 600 or 800 grit paper. If it looks like its working too quickly with 600, go to 800, or if you start with 800 and it seems to be taking forever, step up to 600. After you sand it down so its basically gone, step back to the next grit- or all the way down to 1200- which is as high as you should ever have to go- after that the SS and a coarse wool 3M pad will quickly smooth out the surface.
Remember to always scuff the scratch horizontally- I only go in one direction, and the buffer removes those horizontal scratches. If its a horizontal scratch- I go just slightly diagonally to it. And make longer passes- short intensely sanded areas will show- longer and softer strokes will blend in much better.
I'll post again for deeper scratches and general wet sanding for pitted or rough skin improvement.