If you unlay fiberglass cloth, the heavier the better, you will have strands that can be twisted togather, wet out and laid into the grove. It will take several strands.... I would recommend against turks heads because the water will probably run right over them. The lower angle stroke that I use with a Greenland paddle doesn't produce much drip.  SEEYA Jack

I have built two Greenland paddles, BOTH with drip rings.  Although a Turk's Head knot would look good, more than likely, some water would "roll" past the knot and into your lap.  I took 3/8" cordage saturated in West Systems and made one ring around the blade.  Then, once tacky, I added another ring on top of the first.  This takes care of 99% of the water.  On my next paddle, I'm thinking of adding a thrid ring, all one atop the other. 

To tone down the white line against the varnished paddle, I mixed saw dust (Wood flour), in with the epoxy, creating a more wood-like color. ~BRUCE~

Thanks for the tips.  I used the threads, twisted into a light yarn.  After wetting the groove with epoxy, immersed the yarn into a cup of thickened epoxy and applied the yarn to the groove, taping down the ends.

It was looking a little sloppy, so I used 1" blue painter tape and pulled it across the top of the paddle widthwise.  Just pulled the tape off after 5 hours and shaped the "green" resin. Just a few drips to be cleaned up tomorrow and it looks great.

Thanks for your timely help.