Love the DIY attitude in this thread! I am pursuing a basement renovation, been gluing xps insulation onto concrete walls, and carving out chunks for the oddball sections. Looking at that scrap pile and reading these posts got me thinking ... maybe should try making a board for my foil! I have surfed for a long time and always considered making a surfboard too much ... moderately easy to make a crap board, probably beyond me to make a good one. But foiling is a little different, the board is mostly a platform to support mast, design-wise it needs to be water tight, float for water start, and able to handle touchdowns. A lot less hydrodynamics involved than a surfboard. Hmm.
Currently I am using an old surfboard. I just drilled holes and epoxied in some carbon inserts for the mast bolts, then use plastic plates on top and bottom to bind it together. Seems to be working ok, but the board is a little too long and little too narrow, tends to sink the nose on touch downs. Also, there's a pre existing flex in the mid section that will eventually be the end of it. So....a better board may be in order.
Anyways, a few questions about inserts -- the rectangle cut out for the mast is to replace with wood (or higher density foam), to give the mast something solid to bolt to. Is the fibreglass layers over top and bottom of this enough to hold it in place? Any risk of the wood pulling out of the hole, stripping off the fibreglass? Or does the sandwich of fibreglass/wood keep it in place?
I assume this is how it is done....just never really occurred to me there's wood inserts in these boards. I guess an alternative design is like the surfboard I am using ... the epoxy tubes keep the deck from compressing, the wood stringers keep it from pulling out of the board.
Do the inserts need any water proofing inside the wood holes, to avoid water getting into the wood or sneaking between fibreglass and wood into the foam? Or minimal enough to not worry about?