Hey Bob, I spent last weekend at Johns, playing with his brush tool. I can’t remember who made it, some guy from England who also made vises, John has a couple made by him. It works great but is pretty short. I know it’s old. Wish I could remember the name of the maker
I have one. I make a few brushes a day, predator sized stuff. I would honestly recommend looking into a dedicated unit of sorts. It is easy to use once it is set up, but that can be a little tricky. And, you're either giving up a vise or having to put it back together whenever you want to use it. I had to sand down the tray post to make it be able to fit through the metal component. having the spring adjuster on a thumb screw would be preferred. At the end of the day it is just a vise add on and it feels like such.