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).
Rig tests on Hoffmann 25/30 steering rollers following a previous failure.
| Identifier | ExFiles\Box 159\6\ scan0023 | |
| Date | 15th July 1937 | |
| To HPS.{Horace Percy Smith - Experimental Factory Mgr} from Rm{William Robotham - Chief Engineer}/FJH.{Fred J. Hardy - Chief Dev. Engineer} c. W.Bell. 137X Rm{William Robotham - Chief Engineer}/FJH.{Fred J. Hardy - Chief Dev. Engineer}12/AP.15.7.37 STEERING RIG TESTS. The first Hoffmann made 25/30 steering roller failed on rig test in a short time, apparently because all the balls were not of the same size. We therefore wish to rig test a further six of these which we have checked for ball size and preload, in order to make sure whether or not they are satisfactory. We have handed the six rollers to W.Bell. Will you please fit these to the rig gear as the tests proceed, and, when dismantling rollers which have failed, will you please make a point of keeping the balls from the two ends of each roller separate. No machining is involved as the bore of the inners is already 0.500". Will W.Bell please test roller No.7. - 8 first as we have weighed every ball on this roller. Rm{William Robotham - Chief Engineer}/FJH.{Fred J. Hardy - Chief Dev. Engineer} | ||