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).
Unnecessary slack in gearboxes and the cause of chunking.
| Identifier | ExFiles\Box 94\2\ scan0115 | |
| Date | 12th December 1936 | |
| RHC.{R. H. Coverley - Production Engineer} from Rm{William Robotham - Chief Engineer}/Gry.{Shadwell Grylls} c. Hdy.{William Hardy} 328 Rm{William Robotham - Chief Engineer}/Gry.{Shadwell Grylls}8/AP.12.12.36. P.3. GEARBOX SLACK Confirming our conversation with you, we do think that there is unnecessary slack in gearboxes, due to the present method of lapping the mating teeth of the 3rd. and 4th sliding piece with the 3rd. speed driven gear. When first tried on a mandril these can be tight in one position and slack at 180°. It is impossible to stone the offending internal teeth. The consequent lapping to ensure no tight places means that in other positions there is excessive slack. We know that slack in the sliding piece either on the shaft or in the teeth is the main cause of chunking. Is there anything that can be done on the manufacturing side to overcome the trouble.? In connection with the chunking trouble we think that measurements should be taken on all boxes of the accumulated slack in 3rd. and 2nd. Having established a standard acceptable to Mx.{John H Maddocks - Chief Proving Officer} no boxes would then be turned down by him for this trouble. Rm{William Robotham - Chief Engineer}/Gry.{Shadwell Grylls} | ||