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Gerkin Head
18-01-2008, 04:07 PM
G'day All,
Was pulling out of a jetty and the back side brushed decent against the jetty. Jetty was lined with the grey plastic edge. It's left a nice graze on the side of the boat and I can't scratch it off like I have in the past. It feels smooth but the series of scratchesl appear. The colour of the hull where the scratches are is black. I'm hoping that there may be a simple way of rubbing these scratches out. There are no dents or chips. Just fine scratches...

Look forward to your advice...

Cheers

Roughasguts
18-01-2008, 04:27 PM
WD 40 sometimes works well as a scuff remover.

Grand_Marlin
18-01-2008, 04:29 PM
can you get us some pics?

cheers

pete

Gerkin Head
18-01-2008, 05:05 PM
Pics attached..

steve99
18-01-2008, 05:28 PM
Hey Gerkinhead, Try 1200 grit wet and dry sandpaper. Do a small area first,just in case the gelcoat is thin in that area . If the scratches dissapear you will have to buff the area will a electric sander and cutting compound to renew the original gloss finish.
Alternatively, just try cutting compound and a sander. Minor blemishes are easily removed this way
cutting compound is avaliable at marine outlets or fibreglass suppliers
I have worked with fibreglass all my working life and the wayI mentioned is the best way to remove those marks on your boat

TheRealAndy
18-01-2008, 06:22 PM
I would use a fine cut polish, if that doesn't work use a slightly heavier cut, then as a lust resort go a real fine sandpaper. You would be surprised, but sometime even the old meguires paint cleaner will remove scuffs like that.

steve99
18-01-2008, 06:24 PM
Hey Gerkinhead In he previous post I said electric sander, I meant electric polisher. The type panel shops use to buff cars after a respray.

Cheers steve99

Grand_Marlin
18-01-2008, 06:41 PM
G'day again Gerkin,

Black is the worst to work with ....

It is hard to tell by the pics, but is the scratch right through the black and into white underneath?

Or is it just a sccuff on the black?

If it is just scuff marks, then depending on how deep, steve is right in what he says.

If the scratch is through the black, then it has to be filled, not sanded.

Depending on how deep the scratches are will determine what grades of wet n dry you use ... sure, finish with 1200 ... ,aybe even 2000 on black, but you may need something a touch heavier if they are deep.

Always use a sanding block so as you dont rub dents or holes into the gelcoat

If you have an electric polisher - great, if not, use the 1200 till it is smooth, then use an automotive cutting compound, then finish with an automotive liquid wax / polish.

This will take a bit of time by hand as the black will show any laziness in polishing.

Blackened is our resident detailer / polisher if you need a hand.
also, you should be right, but if you are not sure, I do a bit of touch up work on gelcoat (Valet Boat Services)

Cheers

Pete

Dean1
18-01-2008, 07:50 PM
Hey Pete i was in line 1st when are you gonna touch up my scratches ;D ;D ;D

Grand_Marlin
18-01-2008, 09:09 PM
Hey Pete i was in line 1st when are you gonna touch up my scratches ;D ;D ;D


I had it booked in for last week ... and I forgot ... you have to go to the back of the line :o ;D

Soon Dean, soon ... I drew the short straw on the "no more kids" operation ... so I am suffering at the moment :'(

Cheers

Pete

dnej
18-01-2008, 09:59 PM
Oh dear Pete.Hang in there buddy.
Wondered why you didnt answer my email to you.
David
PS more ice.

Gerkin Head
19-01-2008, 03:39 PM
Thanks for all the tips guys..
Can you tell me what actually makes up the gelcoat ? These scratches feel quite smooth to touch so I'm wondering how deep they actually are... Does the black colour actually sit under a clear coat or is the black the outer colour ? If so, how thick is the colour in general ??

Cheers

steve99
19-01-2008, 04:14 PM
Hi Gerkinhead,
Generally gelcoat is only about 1-2mm thick ,any thicker and it would crack and craze. Your boat is different to most because it has 3 colours on the hull,so its hard to tell whats under that black section.
From what I can see in pictures,those marks would probably buff out with good cutting compound/polish -only use the 1200 wet/dry sandpaper (used wet) as a last resort.
If what you said is true, and the scratches are smooth, you should not have too much trouble restoring the gelcoat. Its usually deep scratches which are the hardest to repair.
Cheers steve99

Grand_Marlin
20-01-2008, 08:32 AM
Good advice Steve,

If you, or anyone, has deep scratches - always fill them, dont try to sand them out as you will nearly always end up with holes / depressions.

Cheers

Pete