How to fix tiny holes in gelcoat on deck

WalshamUK

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I have a Beneteau Oceanis 361 with a white hull. On the deck, several sections have a bobbled surface which provides an anti-slip surface. On one of these anti-slip areas, just forward of the cockpit, there is an anti-slip section where many pinholes have appeared, some of which are quite deep and the fibreglass underneath is visible. This area with pinholes is about 20cm by 30cm, and the tiny holes make it look as if the gelcoat has developed some sort of disease. The rest of the boat is OK.

Does anybody have any good ideas for how best to restore this area?

Keith
 
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Quite common with those boats (and indeed many others with that kind of finish). Caused by air bubbles in the laminate hidden by the gel coat when the moulding is finished. Over time the thin gel coat gets worn or knocked off, particularly if pressure washed. Suggest filling the holes with a drop of epoxy and finishing with Plastic Padding gel coat filler. You may find just the filler on its own will fill many of them. Won't be easy to easy to get a super good finish because of the texture, but should look better than the little holes.
 
When you say the gelcoat is visible underneath I'm a bit confused. Isn't the pattern in the gelcoat? Do you mean the laminate is visible underneath?
I had lots of tiny air bubbles in gel coat that broke through. If they are really tiny you won't get thick filler like plastic padding in, easier with thinner gelcoat (or flowcoat/topcoat) which you can get in umpteen shades to match the boat from http://www.ecfibreglasssupplies.co.uk/ very reasonably.
 
When you say the gelcoat is visible underneath I'm a bit confused. Isn't the pattern in the gelcoat? Do you mean the laminate is visible underneath?
I had lots of tiny air bubbles in gel coat that broke through. If they are really tiny you won't get thick filler like plastic padding in, easier with thinner gelcoat (or flowcoat/topcoat) which you can get in umpteen shades to match the boat from http://www.ecfibreglasssupplies.co.uk/ very reasonably.

Sorry, my error. The fibreglass underneath is visible.

Keith
 
A friend has a repair done to a textured/non-slip deck. A filler was used but that left a flat finish.

Another friend set to with a small file putting the diamond pattern back, it wasn't perfect but it was less noticable than the flat area.
 
A suggestion: Pressure wash then allow to dry thoroughly. Use flowcoat as mentioned but warm it before mixing, then mix very small batches, with as little hardener as allowable. Use a syringe with a blunt modeller's/oiling needle to get the gel into the voids.

You'll need a lot of syringes & needles as the jollop will inevitably go off prematurely.

Try it first with room temperature flowcoat, but it may prove too viscous.
 
Use proper gelcoat (add wax) or flowcoat.
'Gelcoat filler' seems to go grey after a couple of years.
Buy disposable pipettes for the catalyst (ebay), don't guess!
I count how many drops is a cc and then work it out from there.
 
How to do it Geo Non Skid Repairs

Gel coat is a 30mil thick paint and is a convenience for the manufacturer

The Geometric Non Skid area was most likely laminated poorly.

To repair-
Get some matching UNWAXED GelCoat either from a dealer or an internet service

You will need
Clear Gelcoat
Matched Gelcoat
Polyester resin
3/4oz Chopped strand mat
3M Fine line tape or equivalent
Mekp
a sharp chisel
acid brushes
mold release wax
other shop stuff

Make a mold with clear gel and one layer of 3/4 CSMat

Carefully cut out damaged area to make a geometric shape of the damaged surface

Tape it with the fine line tape

Fill the damaged area with catalyzed Gelcoat

Press the mold down with a sandbag ( Lead shot preferred ) I do it with a vacuum bag as a resin transfer mold

put the rest of the catalyzed gelcoat on a piece of aluminum foil so you can pick at it to know when it is hard enough

Carefully remove mold before maximum hardness occurs and trim with same sharp chisel

do not bother with a dremel

Best to practice a couple of times

Good Luck

There is a company that advertises in Professional Boatbuilder Magazine that sells repair molds

You will need to look up molding and demolding and release waxes

there will be a light line around the repair the thickness of the fine line tape




I have a Beneteau Oceanis 361 with a white hull. On the deck, several sections have a bobbled surface which provides an anti-slip surface. On one of these anti-slip areas, just forward of the cockpit, there is an anti-slip section where many pinholes have appeared, some of which are quite deep and the fibreglass underneath is visible. This area with pinholes is about 20cm by 30cm, and the tiny holes make it look as if the gelcoat has developed some sort of disease. The rest of the boat is OK.

Does anybody have any good ideas for how best to restore this area?

Keith
 
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