same material???
because: like likes like?
Dunno: similar expansion, same wood no problema, that sort of thing. Wouldn't use a rottable wood like beech dowels, right?
Ready made mahogany dowel is catalog available.

I'm the sort that if I used the buscuit cutter I'd have to hand make the buscuits out of mahogany too. And not only that, I'd have to turn the grain of the inserts so they were vertical to the grain running in the coaming. That's the sort I am, and that's why I'm still doodling around on the boat and not SAILING!!!