For those contemplating making a thick plate of fiberglass as I am doing . . . Don't
My method has been to lay up CSM & 1708/1808 in alternating layers. I was originally thinking about 22 +/- layers. When I get to 3/4" of build-up, I place some plastic sheeting over the fiberglass in the cavity and use the 1" Coosa piece that I cut out as a 'tamp' and apply some weight to flatten the fiberglass out, so that it is even. Here is a picture of the cavity filled to 3/4" , 'flattened', and cured. . . . It has about 1/4" more to go to be level with the surrounding Coosa.
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Since my shop is fairly cold for fiberglassing (60˚F), it takes a while for the resin to 'kick' . . . but once it does . . . holy cow . . . quite a bit of exotherm !
The piece gets up to about 120-130˚F.
After curing, I add more layers of fiberglass to get up to the 1" thick. What I am finding is that I need about 25-26 layers of glass to get to the 1" . . . probably because of the CSM layer is not as thick as the 1708 and 1808 layers.
I hope to be done today with the inserts and then moving on to the next thing . . . which may be glassing in of the planing surface.
