See knees part 1.
Jon cut two triangles of 3/4″ plywood that I sandwiched together and used as an extension to the bottom of the knee–this was an excellent piece of advice I received from Paul Rosenthal (justifying the cost of having him out for a consultation by itself). He also convinced me (or pointed out) that there was no good reason for putting a reinforcing pad of fiberglass between the knee and the deck. As he explained, the deck should only take the load if the construction is wrong–the hull should be taking all the load.
This was my lay-up (so that I remember two days from now when I do the next one):
large fillet of epoxy thickened with chopped glass (a container of ready-made chopped glass from TAP plastics).
Strip of 6oz glass ~1cm
strip of knytex ~2cm
6oz glass ~3cm
knytex ~3in
6oz glass ~5in
knytex ~6in
knytex ~7in
knytex ~8in (4in each side)
6oz glass ~9in
The knytex is a layer of mat and biaxial fabric bonded together; it is thick and extremely strong. It does not like to take corners at all–hence the thick fillet. If not for the thick fillet, the knytex would pull away from the joint and leave a gap (and weakness).
I think the job is strong enough. I am not a fiberglass professional and so I worry about various things, like whether I use too much resin, and other small things, but until someone smarter tells me what to change I have to plow forward with what I’ve got.
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