John, It's not simply a case of lapping - to my understanding it's the position of the pinion in terms of how far into the the meshing gear it's positioned either shimmed out of mesh or reduced shimming to provide the float required with no shimming allowing the pinion further into the drive surface.(depending on bevel box)
These gears seem to be not positioned correctly for the required float but then how adjustable are they anyway
Has anyone blued up the two gears and adjusted in anyway for even wear along the tooth.?
I think it's read that any company involved in lapping in helical gears would have checked and adjusted mesh first.
My own experience is with similar design Moto Guzzi bevel box. This (correctly IMO) uses shims for both pinion and crown wheel mesh.
It's a while since I've done one, but from memory pinion is adjusted first so it's teeth lie across full width of those on crown wheel. The latter then adjusted to obtain central contact pattern within depth of teeth. Maybe just a final check on pinion mesh to ensure contact pattern is central in the other plane.
There was no float adjustment as such, however the back to back pinion support taper rollers were usually adjusted for correct pre-load first via a third set of shims.
