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).
The performance and issues of non-metallic gears in 4-litre, 8-litre, and 6.5-litre engines.
| Identifier | ExFiles\Box 136\1\ scan0068 | |
| Date | 29th July 1933 | |
| Bn.{W.O. Bentley / Mr Barrington} from C1. (Handwritten, crossed out) R.H.C. (Handwritten) Please return Rm{William Robotham - Chief Engineer} (Handwritten) x411 (Handwritten) Cl/HEM/29.7.33. (Handwritten) Sum Noted (Handwritten signature and note in a circle) MHC (Handwritten initials) NON METALLIC GEARS. 4-litre, 6-cylinder. Cause for complaint from owners round about the 5,000-mile mark through knock through excessive back lash. This knock becomes bad at from 7,000 to 8,000 miles average, but, of course, will run much longer if ignored. It must be remembered that there is no adjustment for back lash allowed for in the design of this engine. Erection back lash, minimum possible, just running clearance or around the .002" mark. Gears only whine when tooth angle is incorrect. Tooth wear on Celeron gear is at the point of maximum loading from camshaft. Gears for 4-litre have been cut both by the Power Plant Co. Ltd. of West Drayton and Messrs. E.N.V. of Hythe Road, Willesden. 8-litre and 6 ½-litre. This gear is practically trouble-free. Average life 40,000 to 50,000 miles, then magneto cross shaft oscillation or rattle intervenes. Back lash, minimum possible round about the .002" mark. There is an allowance in design for an adjustment of mesh or back lash in this model; we in Service find this extremely useful. Gear wears at the three points corresponding to the drive, which is as one would expect. Gears have been cut by the Power Plant Co. Ltd. of West Drayton and Messrs. E.N.V. of Hythe Road, Willesden. The Works Manager, Mr. R.E. Hughes, is the man who deals with all our questions of gear cutting. C1. | ||