Toggles work well on hard boats, and they can be a nice compliment because the wood can accent the wood of the hull. They hold things solidly, because they don't stretch. Cunningham says to make the holes in the toggle 1 1/2" narrower than the rope attachment points. I used polyester rope from a marine supply store that does not stretch. That's pretty important, or the system won't really work. Same goes for your knots. The tension on the ropes comes from friction between the holes in the toggles and the rope. You'll need to find the right diameter drill bit so that there is some friction. Enough so that it stays put, but not so much that you can't move it. If you want more info you can look at Cunningham's book. There's a huge variety in what works when you look at historic boats, so if your first try doesn't work, just untie the rope and make the holes in the toggle closer together or further apart. It's a pretty simple thing to experiment with.

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