How to fill a skin fitting hole properly?

[prv]

I was taught to tape a mirror coated in wax on the outside

Presumably only useful on flat panels, though?

I did something similar to fill a six-inch circular hole on a gently curved piece of cockpit moulding. East Coast Fibreglass sell sheets of wax, which you can stick to a flexible board (eg thin hardboard) and then clamp over the hole. Fill from the inside much as you describe.

Pete

 

[late-night-lochin]

Do not attempt this as a first GRP job

Hi
I used to sail a wooden boat but now have my first fibreglass boat, so have no experience whatsoever working with fibreglass, epoxy and all things sticky! However, I can usually turn my hand to most things, so feel okay about doing the repair myself, once I know the drill.
Thanks for all the links, I will take a look at those. A chap in the boatyard reckoned I should use polyester resin and matt, as the boat is built of grp back in 83. Is that correct, or should I use grp matt circles and epoxy?

It's not just the fibreglass work it's sculpturing with an angle grinder as well.

Start working with GRP by all means but where you can't see it.

The good news about GRP is that if it all goes wrong, you can grind it out and start again.

The bad news about your job is if you don't get it dead right - it will be a **** up!

You will know when you are sufficiently competent and confident with GRP to tackle a job like this because you won't have to ask questions about it.