I glued three pieces of wood together: two walnut and one birdseye maple. After I let it sit for a day, I started shaping it to find out what kind of brush was inside. At first, I didn't know which was the top or bottom. I only knew that once I made the hole, then I would know. I ended up cutting about .4 inch off one end. A 24mm Maggard synthetic knot will go in this handle. It is scheduled for arrival on Monday, May 2.
Updated: April 2. 2016
The Maggard 24mm synthetic knot arrived today, and I was able to set it in the handle with silicone.