The thread turning

Thread turning is a demanding process in which good chip control, stable cutting tool life and stable part accuracy can be difficult to achieve.

The thread turning tool processes threads on the workpiece by making multiple turns. By dividing the entire depth of the thread into a series of small depth cuts, the sensitive tip radius of the tool will not be overloaded.

1. Turning of external thread

Compared with internal thread turning, external thread turning is usually simpler and requires less cutting tools. A number of different approaches can be used to obtain the desired results.

External thread turning considerations:

 Feed rate and pitch must be equal

 Choose sufficient threading threading runs and depth

 Avoid forming chips that can clog the tool and/or parts

 Avoid vibration due to long cutting tool overhang and slender parts

 Point and center high

2. Turning of internal thread

Internal thread turning is more demanding than external thread turning because it requires higher chip removal efficiency and usually requires a more slender tool.

Considerations for internal thread turning:

 Use a left-handed tool for right-handed threads and a right-handed cutting tool for left-handed threads (reverse threads) to help chip removal, especially for blind holes. However, this also carries a higher risk of tool bias.

 Use the modified side feed to create a spiral chip that leads easily to the hole entrance

 Choose sufficient threading threading runs and depth

 Avoid vibration caused by long tool overhang

 Point and center high

 If you need long cutting tools for overhanging, use carbide or damping tools to minimize vibration