PRACTICAL WORKSHOP TOOLS

Quick engineering calculators

Fast metric calculations for common machining decisions. Use the results as a starting point, then check the tool maker’s data and the limits of your machine, holder and setup.

Open calculators

METRIC · NEW ZEALAND WORKSHOPS

Useful answers.
Without the hunt.

Enter the values from your tool data or job sheet. Engineers HQ does not replace the tool manufacturer’s cutting data, but these calculators make it easier to turn that data into practical machine settings.

CALCULATOR 01

Milling speed & feed

Calculate spindle speed and table feed from cutting speed, cutter diameter, flute count and chip load.

Spindle speed3,820 RPM
Table feed611 mm/min
Cutting time9.8 sec
Formula: RPM = Vc × 1000 ÷ πD. Feed = RPM × flutes × chip load.
CALCULATOR 02

Metric tap drill

Estimate the common starting drill size for a standard ISO metric thread.

Estimated tap drill6.75 mm
Formula: nominal diameter − pitch. Confirm the drill against the tap maker’s recommendation, material and required thread percentage before machining.