Milling Calculators

Thread Milling G-code Generator

Generate a simple thread-milling G-code draft for internal or external 60-degree threads.

✓ Runs in your browser↔ Metric and inch unitsƒ Formula shown
01

Enter machining data

Default values are examples. Replace them with your actual setup data.

03

Formula and engineering notes

Formula / logic
Helical interpolation: one 360° circular interpolation moves one pitch in Z. Internal thread cutter-center radius = (thread major diameter − tool diameter)/2; external thread cutter-center radius = (thread major diameter + tool diameter)/2. Verify controller syntax before machining.
Engineering disclaimer: these tools are for estimating and planning. Verify production parameters with toolmaker catalogs, machine limits, material data, and applicable standards.

Frequently asked questions

Can this result be used directly on a CNC machine?

Use it as a starting value only. Check the tool manufacturer data, machine limits, workholding, coolant and material condition before production.

Which units does the calculator support?

The calculator shows the units beside each input. Select metric or inch units where the page provides a unit-system control.

Why can shop results differ from the calculation?

Tool geometry, coating, runout, rigidity, chip evacuation, material hardness and machine power can change the practical result.