I noticed in the Thread.xls that the taper angle for a NPT thread is listed as 3.5798°. My handbook says that the taper for American National Standard Taper threads is 3/4in per foot. This calculates to 3.576334° for a difference of only .003466°.
What is in the chart is close enough for me, but I was wondering why the wrong value is in the chart? All the other values for the other columns are exactly like the Machinery's Handbook except for this.
Am I missing something?
Thanks