DISCLAIMER HOW TO CALCULATE EXTERNAL PIPE THREADS: Is a program to calculate the taper and threads on CNC Machine. Just choose the size and press enter. The program has been updated (1/28/2023) to include 1/8-27, 1/4-18, and 3/8-18 pipe OD threads. Here is what is displayed: Taper Small End= Taper Large End= Taper Length (L2)= Thread Starting point in X= Thread Starting point in Z= Thread Length (L4)= Thread Height= 10 Sizes from 1/2"-14 to 4"-8. All Calculations are based from the Machinery's Handbook 29th ed. and the program ME ThreadPal by Close Tolerance Software. User should back the offset for the Thread tool by at least .010 then move in accordingly. I have tested these as best I can but the user should also do their own testing. You will also get a PDF of the program. Use email account on your iPhone, open with GrafNCalc83. You should receive a message "Imported Successfully". Watch how this program works BUY NOW for $1.35 : Please provide the email