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).
Drawing PD.414, showing a .035 correction for the 1st and Reverse gears on the B.V. B.50 and Silver Wraith gearbox.
| Identifier | ExFiles\Box 136\2\ scan0076 | |
| Date | 5th April 1939 | |
| c. Rm.{William Robotham - Chief Engineer} 1153. DA.{Bernard Day - Chassis Design}15/G.5.4.39. B.V. B.50 and SILVER WRAITH. GEAR BOX. Herewith is PD.414 shewing the 1st and Reverse Gears with .035 correction. This gives an increase in strength and is especially desirable in gearboxes with standard ratios, where the 1st. speed pinion is more highly stressed than in overdrive boxes. As it is merely a modified tooth form, it is suitable for all boxes as soon as it can be brought on. Any standard ratio box being prepared for test should have these teeth. Would BY/CRL.{C. R. Lisson} check for clearance in the box, though we believe all is clear. DA.{Bernard Day - Chassis Design} [Handwritten in blue ink: VARY] | ||