The Wraith gearbox, discussing a trial for the toothed coupling comparing 'V' serrations with Fellows involute teeth.
| Identifier | ExFiles\Box 8\11\ 11-page083 | |
| Date | 10th June 1937 | |
| SECRET. Copy to Mr. [redacted] Mr. [redacted] Rm. {William Robotham - Chief Engineer} [redacted] Hcp. [redacted] Je/Th. [redacted] Mr. Goodall. 628 WRAITH GEARBOX. Referring to the toothed coupling of the extension shaft at the back end of this box, it has been suggested that the teeth should be "V" serrations in order that they may be left soft. We think that they will be satisfactory soft and also that the present Fellows involute teeth should be tried soft before we assume that we must use the more costly "V" serrations. Theoretically the contours of the mating teeth are the same and, therefore, there should be as much area of contact with Fellows teeth as with "V" serrations. The material for the coupling and the shaft should be made S/N. Brinell 286-311. Will you kindly instruct for trial accordingly. E {Mr Elliott - Chief Engineer} /HDY. {William Hardy} | ||
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).