Sizing Tool - Robert Sorby

The sizing tool is used in conjunction with a cutting tool to ensure accurate and consistent diameters of up to 75 mm. The tool is secured onto the cutting tool using the two thumb screws.

Here's how to use it:
Use a steel ruler to set the cutting tool to the desired size, and lock it in place by tightening the wing screws. Roughly cut the wood to about 5 mm from the desired diameter using the cutting tool. Apply a backward and downward pressure with the sizing tool to achieve the precise final diameter.