Start with limits
Record tool maximum speed, spindle range, diameter, flute count and manufacturer recommendations.
Create a test sheet
Record material, tool, RPM, feed, depth of cut, visual result, sound and temperature. This trace prevents repeated mistakes.
Adjust one variable
Change only one parameter at a time. A formula provides a starting point, not a guarantee of performance or safety.
Important
The stated parameters are starting points. Test progressively on scrap and always respect manufacturer limits.