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).
Failure in the Marles steering cam wheel bearing and proposing design modifications for the Wraith II.
Identifier | ExFiles\Box 153\2\ scan0035 | |
Date | 19th May 1936 | |
To BY.{R.W. Bailey - Chief Engineer} Copy to Rm.{William Robotham - Chief Engineer} Hs{Lord Ernest Hives - Chair}/Nm. REC. Hay/NEY. X1300 F.J. HARDY. R/Ev.{Ivan Evernden - coachwork}1/MN.19.5.36. Marles Steering - All Cars. It has been reported to us that there has been a failure of one of the balls in the cam wheel bearing on the 25/30 H.P. We have just seen the details of a similar bearing for the Wraith II, and notice that the radius of the race is over fifty per cent greater than that of the ball. Some while ago Messrs.Ransome & Marles gave us some information concerning the relationship between these two radii, in conjunction with the ball bearing at the top of the Phantom III pivot, and we made corrections in the design, which were sent to you on N.Sch.4768. You will doubtless be dealing with any modifications required to the bearing of the 25/30 H.P., but as we understand the Expl. Dept. are about to instruct parts for the Wraith II, we would like to make suitable modifications to the designs for that car. The ball diameter called for is 15/64ths.ins. and to be comparable with the policy adopted for the Phantom III steering pivot the radius of the race should be about 4% bigger than that of the ball. We therefore suggest that the radius of the race, which is now detailed as .1875", should be made .122". Ev.{Ivan Evernden - coachwork} | ||