Machine guides › General milling machine

How to operate a milling machine

General steps that apply to most manual mills. Your own machine’s manual comes first.

Before you switch on

• Clear the table of loose tools and swarf. Check the vice or clamps are tight and the work is held firmly.
• Check the cutter is tight in its collet or holder, and that the drawbar is secure. Remove spanners from the drawbar.
• Oil the slideways and any one-shot or oil points your manual lists.
• Lock any axis you are not moving. Check the guards and emergency stop. Wear eye protection; no gloves, loose sleeves or jewellery near the spindle.

Setting the speed

• Work out the speed from the cutter diameter and material with the RPM calculator.
• Change belts, back gear or ranges only as your manual describes. On many mills, changing between direct drive and back gear must be done with the spindle stopped; check your manual.

Setting the feed

• Use the speeds and feeds calculator for a starting feed per tooth.
• Climb milling on a machine with backlash can pull the work into the cutter. Conventional milling is the safer default on manual mills.
• If power feeds are fitted, set the stops and know how to disengage them before you start.

Cutter and workholding safety

• Never hold work by hand for milling. Use a vice, clamps or a fixture.
• Never reach past a running cutter or clear chips while the spindle turns.
• Change cutters only with the spindle stopped and the machine isolated if possible.

Shutting down

• Withdraw the cutter, stop the spindle and isolate the machine.

Cleaning and oiling

• Brush swarf away; don’t use compressed air. Wipe and oil the table, slideways and leadscrews.
• Follow your manual’s lubrication chart for oil grades and intervals.