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 from Hardy Spicer & Co. discussing design and stress remarks on parts for 'Rippletto' and 'Myth' models.
| Identifier | ExFiles\Box 114\1\ scan0256 | |
| Date | 7th November 1939 | |
| c EV.{Ivan Evernden - coachwork} 1015- HARDY SPICER & CO., LIMITED. TELEPHONE BIRCHFIELDS 4504-9. (6 LINES) TELEGRAMS & CABLES AUTOJOINTS-BIRMINGHAM CODE: BENTLEY'S PHRAZE LONDON OFFICE 54, St THOMAS STREET LONDON. S.E.1 TELEPHONE HOP 0703 OUR REF. JAD/MW YOUR REF. Rm.{William Robotham - Chief Engineer}3/MH.{M. Huckerby} Manufacturers of HARDY SPICER UNIVERSAL JOINTS AND PROPELLER SHAFTS - GENUINE HARDY FLEXIBLE COUPLINGS BRITISH BOUND BROOK OIL-LESS & COMPO OIL-RETAINING BEARINGS ALL COMMUNICATIONS TO BE ADDRESSED TO THE COMPANY Registered Office and Works BIRCH ROAD, WITTON BIRMINGHAM-6 ENGLAND 7th November, 1939. W. A.{Mr Adams} Robotham Esq. Rolls Royce Limited. D E R B Y. Dear Mr.Robotham, Thanks for yours of 1st inst. We have gone through the details shewn on both prints. In endeavouring to check some items we have had to estimate the top Gear Torque because you only supplied us with low gear torque. We arrived at 1150" lbs for Rippletto and Myth. We agree that the small centre is suitable for tooth pressure. We would like to make a few remarks: Rippletto is alright for Tube but the Torque from engine taken in conjunction with Traction Torque, is too high. We should expect failures here and we cannot suggest increasing only the parallel portion of shaft because it would change the ratio of this part and the splines. The bending stress is not too high but added to the Torsion makes it worse. On the Myth, we feel it could be profitably lightened by using a thinner tube, one of the standards being 5/32", and we would prefer this as it is as easy to get as the 7/32". Spring Pads are shown on the Rippletto but not on the Myth. Are these to be alike? Also are there any shock-absorber Brackets needed because they should be welded on before assembly. As regards prices and delivery, we have discussed this and arrived at the conclusion that even the samples should be made up by Spicer and prices based on their production. -1- | ||