Choose a material family and basic cutter geometry to generate a quick starting estimate for cutting speed, RPM, chip load and feed rate.
What automatic mode does
Automatic mode is designed for the first calculation when you know the broad material family and cutter geometry but do not want to assemble every formula by hand. It uses a small reference table of illustrative starting inputs and converts those inputs into RPM and feed.
The reference values are intentionally presented as starting estimates. They are not a replacement for a toolmaker cutting-data table. A real production job should use the exact tool, grade, coating, engagement and machine information available from the manufacturer.
How the material selector works
Choose a material family, enter the cutter diameter and flute count, then calculate. The calculator supplies a reference cutting speed and chip-load value for the selected family. Those values are visible so the user can audit the starting estimate rather than receiving an unexplained number.
Changing from metric to imperial changes the displayed units and the calculation conversion.
When to switch to manual mode
Use manual mode when the tooling catalogue gives you a specific cutting speed or chip-load range. Manual mode is also the right choice when the operation has unusual engagement, a special cutter geometry, a hard material condition or a machine limit that requires a custom starting point.
Automatic mode is most useful for quick estimation and learning. Manual mode is better for controlled production setup because every input can be tied directly to a documented source.
Step-by-step workflow
Select the material family closest to the actual workpiece.
Enter the actual cutter diameter and flute count.
Review the reference cutting speed and chip load shown by the calculator.
Calculate RPM and feed.
Compare the result with the tool manufacturer data and machine limits.
Adjust the inputs manually if the actual tool data differs.
Run a controlled test and document the validated condition.
Frequently asked questions
Are the automatic values universal?
No. They are illustrative starting references. Use the exact manufacturer data for production.
Can I edit the automatic cutting speed?
Use the manual feed-and-speed calculator when you need to enter a specific manufacturer value.
Why show the reference values?
Transparency lets you see which assumptions produced the result.