We have added an interactive Clearance Drill-Tap Drill Chart as an engineering & machining resource when working with American National Thread Machine Screws. Check it out at MakeTrix Tap Drill Chart. For reference, we have included the hole size equation for American Unified Thread form. This equation computes the recommended size of the tap drill hole for any chosen percentage of full thread depth. Please note that the Percent Full Thread parameter must be entered as a decimal. For example, a 50% full thread value would be entered as 0.50. Once the hole size is calculated, one chooses the tap drill size closest to and less than the calculated hole size.
Also note that we have added an new menu called Tools to the MakeTrix header. We will be adding more free interactive tools and resources to this menu in the weeks and months to come. The Chemical Compatibility Chart navigator has been moved to the Tools menu.