If I am to finally understand what you need to do, I think you are trying to make a drilling jig for a #80 drill so you can place the jig over one end of a broken staff, and drill a hole into the center of the staff for a new pivot. First, you need to have the proper piece of steel to do this. You can purchase a 1/16″ x 1″ x 18″ piece of O1 ground flat stock from and industrial supply house (MSC, McMaster Carr etc.) for about $12.00. This comes in a soft, machinable state and can be hardened by you after the machining is completed. Second, you need to have the machinery in order to do this. Third, the odds of putting a hole dead center into the end of a staff are about zero. What I would recommend instead would be to take a short piece of drill rod that is slightly larger in diameter than the staff and sink a short hole into the end that is about 2/3 the diameter of the staff. Next, turn the end of the staff to the diameter and length of the hole for a good fit. Test your fit and readjust your turned end piece for a perfect fit. The bottom of your new part should line up perfectly on the shoulder of the turned staff. Once your fit has been achieved, harden and temper your part to the correct pivot hardness. Next put a small amount of LOCTITE on the turned staff and press the two parts together. Allow the LOCTITE time to cure as per directions. You can not turn the new part down to the outside diameter of the staff and turn a new pivot.