desperately need fiberglass help

[panhandle]

I need some help.

I removed my windlass in preperation for a new one and have to patch the old hole.

I would like to know how to calculate the number of layers of fiberglass needed for the patch? My deck is wood core with 5/16" thick glass and gelcoat on top.Locally, I can buy 6 oz cloth and matt(not sure what weight).

(5" hole left from windless) I routed out the deck, down to he bottom skin about an 1" wider than the hole, to receive the wood patch and beveled the fiberglass at a 12:1. I cut the 6oz cloth into consecutive smaller circles, about 12 pcs total. I wet the hole and the wood plug with epoxy, then used a thickened epoxy and inserted the plug. Then, I wet each pc of pre-cut cloth and stacked them macking a patch (all 6oz cloth).

This is where the problems occured: I transfered the patch to the hole. The patch changed shape drastically while wetting, It wasn't oval now it was round. Once I laid the patch in the hole and started to squeegy, the edges of the cloth started pulling and fuzzing up (but wet). It was an awful looking patch so I pulled the wet glass out and trashed it. I left the wood plug in place and cleaned up the epoxy for another attempt.

First of all fiberglass cloth doesn't hold its shape well but I think I must have over worked it. I feel like I should layup a piece at a time, right in the hole instead of transferring all layers at once.

Any tips would be appreciated.

By the way I did order 1708 biaxial. It will not be in until next tuesday so if it is okay to use cloth, please make me feel at ease.

and .......the new windlass location will no be over the old hole but further aft

thanks

[giantfan]

I am by no means good with fiberglass.... I just tried my first project with it and it came out OK.....

One thing that I did learn while I was doing it was not to squeege the fiberglass.... I had a hell of a time with it doing the same thing... I found that using a cheap paint brush and dabbing it gave me the best results and got it to lay nice and flat with no air in it....

Just a thought.

[panhandle]

thank you, I have to be gentle with it.

[clt_capt]

The cloth will be fine.

Assuming that you are working on a flat surface, I would paint a coat of resin onto the plug and area to be repaired, then put the glass down dry... Then wet it out and work out the bubbles.

You probably only want to put down 1 layer at a time, wet it out and apply the next layer. Also - start from the center and work out to the edges, moving the bubbles as you go.

When you get all of the layers in place, you can cover the whole thing with clear plastic sheeting (heavy drop cloth type - not saran wrap) and work the few reamining bubbles out.

It also wouldn't hurt to add an extra layer of glass or two - you can sand that smooth and may not have as much fairing to do.