Sealing raw fibreglass scrape mark on topside

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Focused1

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Managed to scrape a small part of my boot top down to the glass. It was painted over with antifoul by a previous owner. After scraping, a sand and polish it looks good. But i do have this small deep scrape right into the glass where a new blade was sharper than i thought it was. It doesent look bad but do i need to seal this scrape to stop wicking? It is above the waterline in red gel.
I dont want to start doing a major repair for this small scrape and wonderd if a clear polyester resin from b and q or somewhere similar painted in with a small paint brush would be good enough?
Thanks
 
So i cant avoid filling with gel coat by using clear epoxy resin to just seal the small bit of glass exposed? Filling and trying to match the red pigmented gel is going to be difficult
 
If it is such a small scrape and above the waterline all you need to do is seal it? If you think a clear coating will do that and you can not get unpigmented gel coat I see no harm in trying clear polyester resin though applying it and keeping it in place may not be easy. Sellotape?
Scratches on car paints which come up white can almost disappear with a spray of clear lacquer, which is the normal second protective layer in metallic paints these days, it has the advantage that after you mask around it you can spray every 15 minutes to build up protection. Aerosols in Halfords etc.
If it did not work you can wet sand it off again.
 
Focused1 said:
So i cant avoid filling with gel coat by using clear epoxy resin to just seal the small bit of glass exposed? Filling and trying to match the red pigmented gel is going to be difficult
Click to expand...

You can use epoxy, in fact it will probably adhere better to the existing cured polyester but epoxy is not as UV resistant and will therefore require gelcoat or paint to protect it.

If this will be hidden under the antifouling then no problem with either UV or colour matching.
 
Thanks for the replies, the antifoul on my boat was painted outrageously high. After lifting out a few weeks ago I scraped the antifoul off because it was flakey in places. Underneath i found a nice red pigmented gel coat boot top and the original waterline that is just below the boot top. I sanded and compounded the boot top and it has come up like the day it left the factory. So when i repaint the bottom it will be up to the original water line that is below the boot top. But during my scraping i dug into the boot top gel coat in one place that i now have to look at that for the rest of the time i own the boat. I hate myself for it. The gouge is not all that visible in the grand scheme of things. The scrape is about 50mm by about 2mm but has exposed the glass in the deepest part of that 2mm. Rather than trying to fill and match the colour i was wondering if there was a clear uv resistant alternative that i could just paint into the gouge to seal the exposed glass from moisture.
 
I use Milliput for this type of job. It is used wet, so any moisture in the hull when we are sailing does not matter. It comes in some colours but almost certainly not the red you are looking for. It sticks well and provides waterproof protection for small dings such as those that can result when stern-to berthing for a whole range of reasons.
 
I'd be inclined to touch up with a one pot polyurethane paint of a close colour match since it's above the waterline. B and Q might well provide.
 
The easiest option is to use some clear polyester gel-coat with a small amount of wax additive solution added. Clean the gouge thoroughly and wipe with acetone, applying the gel with a cocktail stick or something similar.

If you can get some Ral numbered colour cards and obtain an approximate match ( red pigments are notorious faders) you could buy some red pigment (0.5 kg minimum) for 10 or 20 pounds.

If you find yourself in central Southampton then you could look me up. I have several different red pigments and would gladly give you a kit for completing the said repair. I feel your pain.
 
Firstly, are you sure the boot top i s Gelcoat ?

If it is, the solution is simple, get some red flowcoat. There are several ready mixed colours here : https://ecfibreglasssupplies.co.uk/category/flowcoattopcoat-coloured-inc-catalyst

You can also buy red pigments, as mentioned above, if you want to get a closer match. It'll certainly match better than clear resin and will be the proper stuff for the job.

Edit, clean the scratch with acetone, apply some flowcoat (this is gelcoat with added wax to make it dry properly) and stick a piece if sellotape over it to stop it sagging. Once cured, remove sellotape and carefully sand and polish.
 
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