Random Orbital Sander for use on gelcoat ?

[STATUE]

I want to sand down some gelcoat I painted on and now need to sand it back - i.e. getting rid of the ridges I have introduced !

Thoughts and ideas please.

 

[Tam Lin]

Wear a mask!

 

[johnalison]

If it's not too big it might be just as quick to do it by hand, then wet and dry.

 

[mainsail1]

I agree. Sanding by hand with wet and dry is much safer as you tend to stop sanding at the right moment.

 

[LittleSister]

Sanding by hand with wet and dry is much safer as you tend to stop sanding at the right moment. . . . .

. . . . or, more usually, long before the right moment!

 

[macd]

I want to sand down some gelcoat I painted on and now need to sand it back - i.e. getting rid of the ridges I have introduced !

Thoughts and ideas please.

Assuming they're something like paint sags, the trouble with sanding is that the abrasion tends to take material off everywhere, so you still end up with a lumpy finish. An approach I've seen used very effectively in Turkey is to apply a thin, fair coat of car body filler over the affected area, such that it fills the hollows to the level of the peaks. Then sand: wet and dry with a pad is best. The filler prevents your over-abrading the hollows, but allows the ridges to be removed.

 

[Minchsailor]

I have found a cheap(ish) palm sander from Wickes is as good as anything. With care and the right abrasive paper a suede like surface can be produced.

 

[STATUE]

Assuming they're something like paint sags, the trouble with sanding is that the abrasion tends to take material off everywhere, so you still end up with a lumpy finish. An approach I've seen used very effectively in Turkey is to apply a thin, fair coat of car body filler over the affected area, such that it fills the hollows to the level of the peaks. Then sand: wet and dry with a pad is best. The filler prevents your over-abrading the hollows, but allows the ridges to be removed.

Thanks macd - does this process mean that in the end you abrade all the filler off or leave the filler in the 'shallows' before painting over?

Sorry, my question looks clumsy, but its the best I can think of at the moment.

I am only pursuing, as the process looks attractive.

Thanks.

 

[macd]

Thanks macd - does this process mean that in the end you abrade all the filler off or leave the filler in the 'shallows' before painting over?

You take off all the filler, so that the final level is the bottom of the valleys, as it were.
As I mentioned earlier, it's not something I've done myself, just observed pros in yards in Turkey.