I purchased this brush handle from Matt (hig789) on the B/S/T awhile ago and when he agreed to sell it to me, he asked that I post pictures of it when I added a knot. I at first bought a TGN 20mm Silvertip knot to use. But when it got here, I decided I wanted a larger knot. The brush I upgrading from a VDH boar I bought at a local drug store (and the one I'm currently using) is a Semogue 730HD. So I went back to TGN and bought a 22mm Silvertip Grade A. That meant I had to widen the knot hole. I can be so incredibly daft sometimes and I started widening the hole with my pocket knife. Don't send me any hate pm's Matt!! When I finally realized how dumb I was being, I grabbed my dremel and slowly did it right.
I did't research very much about loft or any other technical term. I widened the hole and set the knot in and played around with different depths until I settled on one that I "felt" good with. Not very professional but in the end, I'm happy with the combination. I hope my crude way of doing this doesn't make any of you pros sick!