Surface Finish Spiral Bevel Gears - 'Lapped'

[toolman11]

In respect to differential Spiral Bevel Gears does anyone know typically what the surface values should be (Ra / Rt)
Has anyone done any analysis or measuring of this feature of the gear teeth.
Could one also explain typically the way the test was carried out and any findings/ conclusions would be useful

 

[tbuelna]

toolman11:

For case hardened and finish ground aircraft quality (AGMA 12) spiral bevels, I would recommend 32 microinch for flanks and 63 microinch for the roots.

For high performance automotive hypoid gear sets, I usually take the gear sets as delivered and shot peen the flanks (if not already done). It improves the fatigue life and makes a better surface for lubrication at the contact area.

Terry