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).
Letter to Borg & Beck Ltd. concerning faults found in 10A3 and 11A3 clutches following a works visit.
| Identifier | ExFiles\Box 129\3\ scan0214 | |
| Date | 15th May 1936 | |
| X1110 Exptl. Dept. Hs{Lord Ernest Hives - Chair}/Smth.4/KW. 15th May, 1936. Messrs. Borg & Beck Ltd., Tachbrook Road, Leamington Spa. Dear Sirs, Confirming our visit to your Works yesterday, and discussions with Mr. Armitage. (1) We found that two 10A3 clutches which had jaggered badly in motor cars were faulty in that the operating fingers did not all contact the trunnion thrust face simultaneously. On one clutch the error was .030", causing an out of parallelism of .008" on the pressure plate, and on the other the error was .095", or .015" on the pressure plate. In addition, in the case of the second clutch, the fingers were set in by about .125" from the standard position. You have promised to make special arrangements whereby the fingers will be set correctly to .005" in the future. (2) On measuring the poundage of the thrust springs, we found them all to be below the specified figures (147-155). We would remind you that for the 11A3 clutch you have agreed to hold the springs between the mean and high poundage; i.e., 110-115 lbs. (your letter TS/HTB/CC.21.2.36). We had an impression that a similar arrangement had been made in the case of the 10A3 clutch, but can find no record of it. We should like therefore to take this opportunity of asking you to keep the spring poundage between 151-155 lbs. on the 10" model. | ||