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 detailing an early test on a Phantom to cure axle tramping and steering wobble by stiffening the frame.
| Identifier | ExFiles\Box 154\3\ scan0126 | |
| Date | 11th June 1928 | |
| Y3886 ROLLS-ROYCE OF AMERICA, INC. SPRINGFIELD, MASS. OY7.R.6.11.28 June 11th, 1928. Mr. E.W. Hives, Rolls Royce Ltd., Derby, England. cc - Mr. Thomas Nadin Mr. B.I. Day Dear Mr. Hives: RE FRAME - SECTION 7000 I am reminded by a note to write you about a very early test which we made on 12-MC (our first English Phantom) to cure "tramping" of the axle and H.S. steering wobble. This consisted of stiffening the front end of the frame by arranging four point suspension of the engine. (The car at the time being fitted with R.R. friction-type shock absorbers in front and Lovejoys behind.) The front engine bearer tubes were attached to the radiator cross-member by means of packing washers to fill up the gap between the tubes and the cross-member, and cap screws about 1/2" diameter passing into the end of the tubes through the cross-member which was drilled with a clearance hole opposite the end of each tube. The car could be rapidly tested with or without the stiffening effect by tightening or loosening the cap screws. The four point suspension was found to practically eliminate tramping and within the short test no shimmy was developed when the stiffening effect was used. We were not very good at testing for shimmy in those days however, having just survived one or two nasty experiences of it. The conclusion however was that the sensation of "roughness" (in the front seat particularly) due to the more rigid frame was a fatal disadvantage, and in any case the test was only made as a "stunt" to find the possible maximum effect of extreme rigidity. I now notice however that many American cars are attaching the pressed shell of the radiator by a Vee shaped stay of about 3/4" tube attached to one point at the top of the radiator and two points at either "shoulder" of the dash. (Continued) | ||