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).
Mr. Royce's suggestions for improving braking by modifying brake shoe design and length.
| Identifier | ExFiles\Box 26\4\ Scan253 | |
| Date | 27th February 1924 | |
| To HS.{Lord Ernest Hives - Chair} from DA.{Bernard Day - Chassis Design} c. to RG.{Mr Rowledge} S E C R E T X719 DA{Bernard Day - Chassis Design}1/M27.2.24. E.{Mr Elliott - Chief Engineer} A.{Mr Adams} C. RE. BRAKE SHOES. X.9940. X.3409. Mr. Royce has repeatedly urged the use of a longer shoe backwards than forwards to improve backward braking. We are not sure whether you are expected any further in-formation from us on this point. You have designs for joint-ed{J. L. Edwards} shoes longer backwards than forwards, and it seems that there might be some results from these which would guide us as to whether we can expect any improvement from this arrangement. We understand however you are not yourselves favourably impress-ed{J. L. Edwards} with the jointed shoes on account of the wear on the small shoe, and therefore we suggest that the forward shoe should be solid and the backward shoe only jointed. A difference in length of the 2 sets of shoes could be obtained by substituting a solid shoe for the forward lapping shoe on N.sch.1711., and removing the ferodo until there was an angle between it and the cam centre line of at least 30°, the backward shoe remaining jointed with the lengths as shewn on that drawing. The screw stop for the solid forward shoe would not necessarily be re-quired but the present stop might be used. We assume that Mr. Royce principally refers to front brakes in connection with these experiments because he alludes to the effect on jaggering. At any rate it would seem that the experiments might be tried on the front brakes. Unless you are waiting for additional information we did not propose to do any work on this point until we contd:- | ||