So it couldn't be easier! I wanted a 2-band brush, and thought about sending it out. But instead I ordered a TGN 2-band for $23, steamed out the old knot, and set the new one, all within a few minutes. Go figure! I can't wait to break it in.
It used to have a silvertip knot, 24mm in it. That knot popped right out after steaming and I actually restored a different brush using that knot. I used a marine-grade epoxy to attach the knot to the handle. The photo is of the original brush and knot.
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