Ok, shoulder bolts are ground to specific tolerances on the shank. Depending where you get them from, there will be a tolerance class to them like h8 or something. That will tell you what hole size and tolerance you should specify depending on the tightness of the fit you want. Give us a link to the bolts.

This is where geometric tolerance will also come in to play but that may be overkill for your application.


Are you looking to get this made by a chap in a shed or are a pro machine shop?