Thread cutting procedure on the lathe at The MakerBarn.
For great information on thread cutting and other machining procedures, see Joe Pieczynski’s YouTube channel. His thread measuring video is at:
https://youtu.be/be6Q9mm4vEQ

A link to the chart used in this video is below:
http://www.team358.org/files/mechanical/Clausing12inLatheMakingThreads.pdf