: I thought I might strengthen the joint with a fillet. This might allow enough
: strength that I can finish sanding the coaming withoug breaking the it
: from the deck.

That's a good plan. You can get away with a fairly small fillet... like a 1/8" or even 1/16" radius. That will be enough to hold the risers in place and help the fabric lie flat when the time comes. Just re-glue a piece if it breaks off while you're sanding. It will be pretty solid once it's glued all the way around; rock solid after it's glassed and the rim is on.

I hope this helps,
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