Lathes are capable of creating any form thread, including tapered pipe threads, OD, ID, and multi-start. Most threading on a lathe is done with an insert. Several roughing passes that decrease in depth with each cut are followed by one or more finish passes that remove a small amount of material to form a thread that is accurate and smooth.

The motion of the tool and spindle are coordinated by the CNC control so that each time the tool begins the cut pass at the same rotational position.

Figure 8.32: Thread

Rules for Threading