I put a 3mm dyneema into my starboard board. I just drilled a 3mm hole all the way through, then drilled it out a bit bigger on the far side for the knot to fit. put the line through the hole, tied a knot, covered it with epoxy stick, then gelcoat, can't even tell where it was and I've had no issues. I guess you could use regular epoxy but all your trying to do is seal the hole and I wanted to be able to remove it relatively easy incase I ever needed to access it.