On edge of the tips of the paddle, I laminate four layers of 'glass matt strips (which comes out to about 3/16" thick) and wrap it ~1.5" up the sides of the blades. After curing, them tip laminations are faired into the blade contour, then shaped to a rounded cross section. I then coat the last 3" of the blade with epoxy to protect it from abrasion. I found that masking is only partially effective, since the epoxy wicks into the wood under the tape, at least on the cedar I use. Perhaps this is less of an issue with other woods.

So far, this system has proven to be very durable. It's also extremely easy to do. On my next paddle, I may tint the epoxy white to simulate bone tips.