Removing gelcoat scratches

AngusMcDoon

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I have some scratches in my gelcoat that I would like to repair. These range from very minor to some deeper ones, but none of them penetrates all the way through to the underlying laminate.

What's the best way to repair these? Can I make a good job of it as an inexperienced amateur, or should I get it done professionally? What supplies will I need, and where can I get them from?

Thanks for any advice.

Angus
 
some gelcoat with pigment to match, clean the scratches of polish/wax, some use a old can opener to do cleaning, mix up the gelcoat and fill in the scratches and let cure, light sand and polish out. or just use buffing compound on the lighter scratches....just my thoughts.
 
U will need to ask Old salts he will explain it clearly, u do need to put wax in styrene into the gelcoat so its easy to sand as normal gelcoat will not cure in normal atmosphere or cover the gelcoat with silicon tape to remove the air so it cures.
 
Gelcoat repair kit is ready-waxed. The trouble is that while your topsides look white and so does the filler, it's amazing the difference you will see when the two are put together. Last time I did it the filler looked almost battleship grey!
 
Thanks for the replies so far. I hope oldsaltyoz will spout his stuff as well when the sun goes round to his bit of the world.

As these scratches don't go through the existing gelcoat, I was hoping that I could avoid filling and the necessary <font color="red">c</font><font color="orange">o</font><font color="yellow">l</font><font color="green">o</font><font color="blue">u</font><font color="purple">r</font> matching, and instead just take down the surrounding gelcoat somehow, and then polish the whole lot to a shine.

Does this sound feasible, or is filling with new gelcoat the only way?
 
When having a go at some damage in my gelcote I found that it was a good idea to lightly sand the area around the repair first, this gets rid of the layer of faded gelcoat otherwise it shows through the new gelcoat where they overlap.
 
If scratches are small and boat is white,

Wet and dry emery paper will remove the smallest scratches.

Plastic Padding, white obvious, will fill the deaper ones and will not be noticed. Best to clean scrarch with nail polish remover or acitone. Be carefull though, it melts f/glass.
 
G'day Angus,

I totally agree with Snowleopard the big trick here is to match the shade of white.

Also note that any gelcoat repair will be a disaster given time; assume you manage to get a perfect colour match. What happens over the next couple of seasons is that the old gelcoat continues to fade at it's own rate, and that rate will not match the newer material, end result, lines on deck instead of scratches.

If you ran a search on this forum for gelcoat you will get more than enough advice to do the job yourself; however, I would advise you seek out a professional, at least you will have some come back when it all goes to custard.

The inside of the scratches must be spotless and have no contamination, this is best achieved by very carefully mechanically cleaning out the marks and wiping with Acetone.
The area around the repair must be polished and then all wax removed prior to repair.
Sticking a very thin tape each side or the area to be repaired and using it as a guide for removal of surface material when filling will save a lot (if any) of sanding.
I prefer the no wax and a cover strip of very smooth and reasonably stiff plastic (about the same as a wide but thin plastic ruler) to act as an air shield and provide a finish that requires no sanding, just a cut and polish.

Bet I get flamed for this.

Avagoodweekend..........
 
What about polishing out the shallow ones without any filling? Can that be done? What would I use to do it, and would I get a reasonable result? If I used a fine wet&dry paper to get the scratch out, how would I get the shine back?

These are really very shallow scratches, none goes all the way through the gelcoat, and I'd rather leave them there than risk incorrect colour matching.
 
Yes, you can try polishing out fine scratches with a fine grade rubbing compound. Use a rotary disk with a a wool pad - no synthetic material. But the scratches have to be very fine. The rubbing compound looks and acts somewhat like polish but is more abbrasive. Be careful not to overpolish as you can remove more of the gelcoat than you might realise. It leaves a pretty good finish on its own but I prefer to use a simple wax polish afterwards. I have no idea how far into the season it really lasts.
 
This is what I have done with a few deep scratches. If your gelcoat is white, you can try this. I used white epoxy glue for repairing broken porcelain. Not cheap, but if you only have a few scratches to do, it may be the easy way out. Easy to mix. When you sand it smooth, you will hardly know it. As I said, only if your gelcoat is white. /forums/images/graemlins/wink.gif
 
first, dont panic. If you can mix araldite, you can mix and use gelcoat. Protect around the area, and dont overfill, or you will have alot of extra work sanding it all out. You ll need 600-1200 grade wet and dry;just remember, if you use coarse paper you will have alot of reparation getting those coarse sandpaper scratches back out. Safer to start with too fine a grade, and work towards the a coarser one, but still as fine as you can use. Believe me, its harder to get out coarser scratches than it is to repair the crack in the first place!
To really get a polished finish, you ll need some cutting compund/polishes, and a proper polisher. About £40 from toolstation.com, and worth saving alot of hard work.

CLS in cornwall can supply you with all sorts of pigmenst and resins, and these trade quantities are about the same price as the mickey--mouse volume you can get from the swindlery.
For off white, and a reasonable match, its feasible with a little patience, but if you want a true invisible repair, you re going to need the 20 yrs experience of a pro! Around solent , thats probably £350-700 depending on amount of work needed.
 
Remember that the more gelcoat you rub down, the thinner it becomes and therefore the sooner the substrate will appear.

Once this condition has appeared you will have to be thinking about painting the topsides, so don't be too energetic rubbing down to fair in deep scratches, your chequebook won't like it at worst and at best you could end up with a patch of thinner gelcoat through which you can see the darker substrate- self-defeating.
 
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