Reduce setups to cut machining cost

Each time a part is unclamped, turned over and clamped again, the shop spends time on fixturing, measuring and re-zeroing. It also adds a chance of misalignment between features made in different setups.

What counts as a setup

A setup is one way of clamping the part. On a 3-axis mill, everything the tool reaches from above happens in one setup. Features on the bottom need a second setup, features on the sides a third and fourth.

Design tips

• Put pockets, holes and slots on one face where possible.
• Make holes through, so they can be drilled from whichever side is already set up.
• Avoid single small features on a side face; they cost a whole setup.
• Features that must line up accurately should be made in the same setup.

When 5-axis helps

A 5-axis machine reaches five faces in one clamping. The hour rate is higher, but for parts with features on many faces it can still be cheaper than four or five 3-axis setups.