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drevil
22-07-2003, 03:47 AM
Hi All

I was talking to a guy on the weekend about polishing the gelcoat on my boat 'cos it's a bit powdery.

He does this for a living, and he said that he first acid washes it, then machine cuts it and finishes with a hand cut.

Is this okay on gelcoat? I would have thought it might be a bit too harsh. What do you think?

blaze
22-07-2003, 07:36 AM
Hi drevil
When I polished mine, I start to buff it by machine with buffing compound, in the end just finished off with a cut and polish and I think it come up fine. I dont believe you can ever get gelcoat back looking like new, but with a bit of polish every now and then they can look cleaner
cheers
blaze

gavsgonefishing
22-07-2003, 08:44 AM
Dont know about the acid, on a powdery surface, I would cut it back with wet and dry 400-600 grade, then follow up with wet and dry 1000-1200 grade. By this time your arm will feel like lead and as big as popeye.

Machine buff it with proper buffing compound, finishing it off with a hand polish.

I know its a lot of labour on your part, but the result worth the effort

aquarius
25-07-2003, 04:55 PM
Drevil...Mate i have used linseed oil to polish my boat hull and it came up tops....I was told if you apply the oil once a year it will retain a glossy shine.....It will cover up minor scratches and that powdery surface.
Cheers Brent ;)

Big_Kev
26-07-2003, 01:58 AM
Never heard of that one Brent, that sure is a handy one to know.
Cheers Kev.

drevil
26-07-2003, 04:16 AM
Hi Aquarius, I haven't heard that one either. I guess there's no reason why you can't put linseed on gelcoat. Thanks for the tip. ;)

aido
26-07-2003, 04:17 AM
thanks for the tip brent,
if it still doesn't meet expectations,
all is not lost, the cricket bats can do with a bit of an oil ;) .

seriously though, i tried methyl ethyl ketone (mek) and it
really cleans some surface shite off, beware though, too much
and the top coat comes off, think its some sort of mold release wax ???

isopropyl alcohol is milder and cleans well but leaves a residue, good excuse for final polishing any ways. best result seems to be good old wet and dry
paper, elobow wax and a lot of caution like gav says.

that's my experience, and will be trying linseed soon as the front deck still needs some work on its well aged gelcoat surface, not powdery, though it
looks a bit tired in parts.

whatever you do, make sure you do it in good light.
and good ventilation if using solvents etc.

drevil
26-07-2003, 04:28 AM
What about minor scratches? The hull has a couple of minor dings in it and the gelcoat has chipped off showing the fibreglass underneath. The guys at the marine shop where I had it checked out said it was no problem, but might be worth patching at some stage.

I want to do that before polishing the hull. What is the best stuff to use? I saw some 2 part compound at the chandlery. Is that the go? Any special tricks to watch out for or any special preparation before it's applied?

stocky
26-07-2003, 05:39 AM
The use of linseed oil will not hurt the gelcoat. I think though it will have the same effect as amourall that you use on car interiors. This will not clean significantly but leaves a film of oil that hides the imperfections.

blaze
26-07-2003, 08:36 AM
Hi all
My thoughts on linseed oil are that there may be a possibility of it soaking into the gelcoat and if a repair is ever needed it would make the chemical bonding of the repair not adhere as well as it might other wise. I know that some car polish available make car body repairs very frustrating in regard to getting the new paint to stick, i think the polish my panel beater mate bitched about were silicon based (not 100% sure), but seen him nearly rub a pannel to bare metal to do the repaint. It is possible that linseed oil may have the same effect, so be careful
cheers
blaze

harrya64
26-07-2003, 08:39 AM
Hi All not to sure about Linseed oil
But Never and I repete Never use Teak oil On gelcoat A long time ago when I had a Yacht that had grab teak rails on the deak I was oiling them with Teak oil and spilt some on the deak and man it stained so badly I han to repaint the deak .Just thought that I would mention it. Cheers but I am interested in what will work as I have just bought my self a Carrabeen Navagator 15' and it will need some TLC and polish.Cheers Hasa