Help understanding a thread designation.

[danreetz]

I'm new to threadcutting, in fact, new to using the lathe. I just got a 7x10mini. I'm trying to understand what the thread measurement in this image means.

How would I go about cutting such threads on my lathe? What does .535"-40 mean, in terms of thread pitch, and so on? Is there a chart I should be consulting?

[MrWild]

that's a bastard thread. It has a diameter of .535 inches (it is english, right?) and a thread count of 40 threads per inchi. Turn your diameter to ,535, then set up your feed for 40 threads/cuts per inch. the rest is the same old, same old

[danreetz]

By bastard thread, you mean non-standard, right?

I understand the diagram now, thanks!