heavy,medium cut or marine compound?

[DaverDog]

Ok i have a 79 fiberglass starcraft that is heavily oxidized. Should i use a heavy or medium cut compound? or rub it out with polish because of the gelcoat? and an acquaintence of mine mentioned i mite not want to use the regular rubbing compound because of the gelcoat and that i should use marine compound.Wouldnt that be the same as rubbing it out with polish(using a marine compound)?thats assuming the marine compound has a very fine grit...and if a marine compound even exists i dunno...help and thanx guys

 

[gcboat]

Re: heavy,medium cut or marine compound?

Here's a good article :http://www.boatus.com/boattech/casey/01.htm

 

[Sorrento 25]

Re: heavy,medium cut or marine compound?

3M Super Duty Compound and Finesse-It II Polish is working great for me.

 

[cnyman]

Re: heavy,medium cut or marine compound?

While it sounds crazy, I would wet sand with 800grit wet/dry sandpaper(it feels as smooth as notebook paper) and then buff with Mequires heavy duty oxidation remover. Finish with a good paste wax and this will last for at least a year. No matter what compound you use, you will not be able to remove the oxidation effectively(evenly) so it will appear shiny but cloudy in some spots. The wet sanding process is easier than it appears. Just get a rubber sanding block and 8-10 sheets of the sand paper. Cut the paper into strips that fit on the block and wet sand until the surface is really smooth. Stay clear of the hard edges as you can sand through the gelcoat with heavy pressure. Don't worry too much, though, gelcoat is quite a bit thicker than paint. I have used this technique on my 86 SeaRay sundancer and it looks as like new. Good luck.

 

[brodie6]

Re: heavy,medium cut or marine compound?

3M Super Duty Compound and Finesse-It II Polish is working great for me.

I love the 3M stuff. Use a 7" polisher and a foam maguire cut pad and your good to go. Unreal results.

 

[BillP]

Re: heavy,medium cut or marine compound?

It depends on how bad the oxidation is. Sanding with 400-600 wet is for the worst. After the 600 use heavy compound, then a medium and a final buff with polish. You can use finer wt paper but all it does is make more work...heavy compound takes 600 scratches down easily and quickly with a foam pad and 3000-5000 rpm disc. Dupont automotive compound is commonly used in the fiberglass industry on gelcoat so don't worry about something with "marine" on the label. Use a foam pad and plenty of water.

bp

 

[DaverDog]

Re: heavy,medium cut or marine compound?

Ok i have a good idea how im gonna do this now...thanx alot guys and safe boating!

 

[Coors]

Re: heavy,medium cut or marine compound?

I bought an '88 with navy blue gelcoat.
I used 600 grit on a section, and freaked out at the scratches.
Then I got a 1500 rpm angle grinder from harbor freight, and put on a 3m felcro pad, and used 3m compound.
Excellent, it just takes getting used to keeping it running, with less pressure towards to end; to let the same pad finish it off. The pad gets dry and does the buffing.
A different world; not letting it dry to a haze, then buffing.