Katana Umbrella handle

My wife bought a cheap Katana umbrella at Disney World because she likes ninja type swords, but the handle fell off as soon as we got out of the car at home. So I gave it a shot f making a better one. The umbrella shaft is 15mm in diameter and goes 85mm deep into the handle. I modeled the diamond pattern into the handle so that whatever material you use to wrap the handle can be wrapped around it. I used roughly 3m of a 1cm wide thin cotton ribbon for the wrap.

The bottom cap design was taken