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).
Clamping coupling methods and shaft spline clearances, with comparisons to other manufacturers.
| Identifier | ExFiles\Box 124\3\ scan0353 | |
| Date | 9th April 1935 | |
| -3- on parallel castellations and to clamp the coupling endwise by the nut. This is so on the Cadillac and Terraplane. I have no information about the Buick. However, it is very likely that the clamping force is sufficient to prevent movement due to the overrun torque and as the rearmost bearing is relatively infrequently heavily loaded by a journal load there will be little rotation of the race and therefore little endwise wear. The use of a spring washer for the setscrew which applies the clamping force as on the Cadillac ensures that even if some wear occurs the pieces do not become entirely free immediately. We think that we should reconsider the question of clamping as we may be able to get more shaft stiffness by the same means. (see HDY{William Hardy} 2/MN.9.4.35.) HDY.{William Hardy} x We find from the Cadillac service book that the shaft spline clearance for the top gear coupling should be between 1/2 and 1 1/2/1000" when new and should be reconditioned if found to exceed 5/1000" when worn. Our limits allow between 1 and 3/1000" but we understand that by selection this is held down to about 1 1/2/1000". | ||