Very small but numerous (1000s)holes in cockpit....

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Jaguar 25

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These microscopic holes are mostly on the vertical faces inside the cockpit and on the outside of the transom - main portion of hull is OK.

Any advice on how to deal with them or info on possible cause. Boat is 30 years old (Jaguar 2).

Best regards for the season.
 
I had similar on a previous boat. I always assumed they had been just under the surface since the boat was built and gradual removal of the surface through polishing/abrasion had knocked the tops off the bubbles. I tried scraping gel coat over the top but it's virtually impossible to do a decent job. When you try to wet and dry the bits of gel left on the surface you are liable to open more bubbles.
In the end I decided I was the only person who knew they were there so left them. Priming and painting may well be the only real solution.
 
These are probably voids in the original Gelcoat that have been exposed by time and wear on the Gelcoat through cleaning etc. If you can match the Gel colour then they just need filling and sanding back through the grades (finishing with something like 2000 grit). You will need a Gel with wax in that is designed for repairs (flow coat). With the transom the area is small enough to do the whole thing to avoid issues with colour matching.

Yoda
 
Hi
i had the same problem after trying with gelcoat gave up just to many and to small,
in the end i used two pack primer rubed in with a cloth then painted with international paint
to my colour 2001 off white
 
Jaguar 25 said:
Thanks, I'll try filling first on a small portion.
Click to expand...

What you are about to attempt is a bot like putting toothpate back in a tube with your finger, almost a complete waste of time materials and money.

So when you do this, find a small area and first give some stick with a pressure washer, this will open up a few more, then let it dry and wash down with Acetone to remove any contaminants then sand it with 250 grit.

Wash it and wipe with Acetone ant sray on some flow coat (gelcoat with added wax, so no need to cover it). Let it cure for a few days and sand back in stages with wet and dry, start with 800 grit then 1000 grit, finish with a 1200 grit and polish.

It will look like a new boat.

Good luck and fair winds. :)
 
I think the original cause of these micro holes is aeration due to sprayed gel coat in the first place. It was quite common for manufacturers to spray apply gel coat to the mould as this gave a more even coat and better opacity than a brushing type gel coat which often had to be applied in two coats in order to give enough opacity. Unfortunately with air atomised spray guns the air could be driven into the gel coat at points where the sprayer allowed the spray gun to pass too close to the mould. This could often be at deep parts of the mould such as the the vertical sides or top of a coaming or transom.

The effect could not me detected at the time of manufacture unless it became necessary to make a gel repair in an affected area. It them became quite difficult to make the repair as sanding grit and polishing compound could get trapped in the newly exposed aeration holes.

With time and weathering such aeration holes become visible but IMO don't pose any threat to the structure of the moulding as a whole. Personally I wouldn't expend my energy in repairing them unless I was considering painting the complete moulding when I would fill them before applying the paint scheme.

However, if you are still keen to do the repair you would do well to follow the advice from oldsaltoz. I would have come up with something very similar myself.

Good luck
 
Gel coat treatment

If you want to fix the problem I would go for a 2 pack polyurethane paint rather than polyester gel coat as originally used. Polyester really only sticks best to itself when not hardened such that you get a chemical bond. Polyurethane paint will be thinner and sticks better so will better enter the holes and fill them.
The paint hopefully can be tinted to match the gel coat colour just as well as gel coat can be matched.
good luck olewill
 
jfkal said:
Where to get sprayable flow coat?

Thx
Joerg
Click to expand...

If you can't buy it ready mixed you could consider modifying available materials.
For example some manufacturers do a sprayable gelcoat to which you could add 1% to 2% (max) wax solution.
Alternatively you could thin brushing quality flowcoat with a little styrene monomer.
 
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