Describes gear blanks and teeth machined before hardening, when the steel is easy to cut. Green cutting by hobbing or shaping leaves grinding stock for after heat treat, or, for gears not ground, produces the final geometry with an allowance for expected distortion. Green dimensions are recorded so heat treat growth can be tracked lot to lot.
Measure them green, over pins, before they go to carburize, so we can see how much they grow in the furnace.
Also heard as
- green cut
- soft
- pre-heat-treat
Related terms
Hobbing
Generating gear teeth with a rotating worm-shaped cutter that turns in step with the blank.
Carburizing
A heat treatment that diffuses carbon into the surface of low-carbon steel gears, then quenches for a hard case.
Gear grinding
Finishing hardened gear teeth with abrasive wheels to correct heat treat distortion and reach high accuracy.
Hard gearing
Shop term for case-hardened, ground gears, as opposed to through-hardened soft gears that are cut to finish.