I have a butterscotch handle that I'm doing a restore on. The hole is exactly 22 mm in diameter. Dumb question: does that mean I use a 22 mm knot? Or are you supposed to use a knot somewhat smaller than the hole?
The knot should be the same size as the hole. If the hole is 22mm then you need a 22m knot. If you are in between knot sizes, it's worth sanding the hole a little to move up a knot size as opposed to stuffing in too much glue to fit a smaller knot.