I have a one-only job to make a female threaded adapter for a guitar stand. The male thread I have to match is a odd size (near 7/8th's) and is 26tpi. My question is how to determine hole size for single point threading? My idea was to measure major diameter of the male threaded piece and subtract the double depth of 26tpi (.050) extrapolated from the figures found on a Starrett center gage. Is this the way to figure this or is there a better way?
Thnx - John C