Rubbing Compound for Gelcoat Scratches?

[Sea Wolf]

[Tortuga]

I wanted to bring this thread back to the top because I'm trying to repair fender rub damage on my green trim. I've polished, using the 3M fiberglass restorer, and waxed and waxed, but the dull scratches are still obvious:



I also have some scratches from meeting a dock pile (so a C-Dory and a pile go into a bar...). They also disappear when wet, but don't completely buff out:



I'm thinking of stepping it up to wetsanding -- but as my MO is to escalate when confronting a hurdle, I thought I'd seek some additional input.

I believe the scratches are repairable because they disappear when the boat is wet -- suggesting that there is gelcoat under them. But, I haven't been able to get them rubbed out with the 3M. Any thoughts on the wetsanding?

Thanks,

Matt

[Sea Wolf]

Matt-

Since they disappear when wet, you might try one of those "miracle" scratch removers they sell on TV or in auto stores that (I think) is actually a clear acrylic coating that fills in the roughness and picks up the coloring of the pigmented areas around it.

Ron, formerly of "Snoopy C", used an acrylic coating "wax" on his new boat a few months back with great results! See:

Tried a New Product

Joe.

[Sneaks]

Use 600 wet/dry grit followed by 1000 wet/dry grit followed by rubbing compound. Doctor Bob is the absolute best authority on that so if he differs from my technique definitely follow his lead.

I would also consider starting out with 400 grit on the worse ones and working through to 1000 using PLENTY of water. I have several spots on the C-Brat that will be getting "the treatment" real soon now.

It doesn't take a lot of muscle so go slowly and use a rubber sandpaper block or something that's really flat. Pep boys sells a little sanding "kit" with a nice small block and various wet/dry grits 400-1000 I think. Cheap and works great in small areas. Look for it in their paint and sanding product area.

Don

[Tortuga]

Thanks for these suggestions -- I'm wary of the acrylics due to the difficulty in removing and a concern over discoloration or peeling over time in the sun. I'll try the wetsanding under the waterline to see how things go and report back. Thanks for the tips.

Matt

[sjboysen]

Peter,

There a lot of good comments that you can follow on this thread, and I will add mine as well. The depth is obviously the determining factor whether or not to sand or fill. As the gunnel stripe is sprayed in the mold during the initial gelcoat process not after it might be a little difficult to tell if you are too deep or not, a good rule of thumb is that if you can catch your finger nail on the scratch it will be too deep to sand out. If it is just a surface scratch then just buff it out, finesse it works fine, not real aggressive so it may take a couple of passes to get the scratches out. Wet sanding is not necessary if you have access to a Dual Action sander, either or I recommend starting at 400 and working your way up to 800, you don't need to go higher than that as your compound will eliminate the scratch marks and bring forth the shine.

I will be holding a limited size seminar here at the plant October 16th, and I will be going over just this scenario, so if you have any questions don't hesitate to give me a call or send me an email.

Scott

[Tortuga]

Thanks Scott -- the fingernail test is a great place to start.

Matt