I'm in the process of planning my new bench and something I have always wanted is the large 2" - 3" wooden screw to thread into the bench for the vice's.

Turns out I can't find anything for over 1-1/2". Also, I have read that the current ones are not the proper threading for wood.

Does anyone have any ideas or measurements for building your own tap & die. I know there are a few for the wooden thread box but I'm more interested in how to build a tap for an impressive 3" wooden screw.

I'm thinking a wooden dowel with two teeth secured into them at just the right angle but not sure the angle/spacing/depth or even how to properly secure them for the massive torque I'm sure they will see. Once I have the tap built, the thread box should be the easy part.

Thinking more, maybe a single piece of flat tool steel with a tooth ground on each end offset just right and then secured inside a steel bar and tipped with a wooden plug to keep everything aligned.. hmmm