Yeah, I've cord-wrapped an 18 with knurled handles too. Sadly I didn't take a pic of it when it was wrapped.

I used black "Micro Cord" from Atwood Rope company. Looked pretty sharp when done right (took a few tries).

The trick is to keep heavy tension on the cord while wrapping. You pack the loops tight while wrapping with a thumbnail or thin hunk of steel, just takes an extra bit of effort since you only have two hands.