From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Material change for the wheel driver on the 25/30 HP chassis rear hub.
| Identifier | ExFiles\Box 102\4\ scan0102 | |
| Date | 14th May 1937 | |
| BY.15/C.14.5.37. 25/30 HP. CHASSIS - REAR HUB. RE: WHEEL DRIVER. In order to prevent the wheel driver wearing in the mild steel hub and causing knocking in consequence, it is desirable to make the wheel driver in a case hardening material. There is no need to make it in S.Z.N.Cr.{Mr Cra???ster / Mr Chichester} as we have never broken the drivers, our sole trouble being knocking. I am, therefore, arranging to instruct on production, as well as experimentally, the drivers for the 25/30 to be made in S.Z.N.X. The external teeth on the driver must be ground to a smooth finish, as this will practically eliminate the wear between the two tooth surfaces. This should be brought in when ordering any further material. There is no need to scrap existing parts. BY.{R.W. Bailey - Chief Engineer} | ||