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).
Comparing the weight and specifications of Hispano front brakes against E.A.C. and 40/50 HP models.
| Identifier | WestWitteringFiles\L\2Jan1924-March1924\ Scan26 | |
| Date | 1st February 1924 | |
| R.R. 493A (40 H) (SL 42 12-7-23). J.H., D.{John DeLooze - Company Secretary} EXPERIMENTAL REPORT. Expl. No. 42191 1559 7940 REF: Hs{Lord Ernest Hives - Chair}1/LG8 2.24. S E C R E T. HISPANO BRAKES. To R.{Sir Henry Royce} from Hs.{Lord Ernest Hives - Chair} c. to CJ. RG.{Mr Rowledge} c. to DA.{Bernard Day - Chassis Design} E.{Mr Elliott - Chief Engineer} c. to BY? WOR.{Arthur Wormald - General Works Manager} Attached herewith are further particulars of the details of these brakes. Below is a comparison in weight of a Hispano front brake and 40/50 HP. RR. WEIGHTS OF THE EAC.111 AND HISPANO FRONT BRAKES. E.A.C. LBS. OZS. HISPANO. LBS. OZS. Weight of 1 shoe. 3 1 3 6 Wt. of carrier complete with dust cover, cam, pivots etc. 12 11 8 0 Wt. of drum. 24 4 16 9 Wt. of Camshaft or toggle shaft and toggles, springs and bolts. 3 8 3 7 Total wt. of Brake with drum, springs, bolts etc. 43 8 31 6 The total wt. of brake, drum etc. given for the EAC.111. does not include the operating mechanism mounted on the axle. In comparing these weights, it should be remembered that the Hispano drum is 15.75" dia. compared with 15" RR., and the width of the shoes is 2.5" compared with 1.75" RR. The area of Ferodo on one Hispano shoe is 38 sq.in. - on the RR. 28 sq.in. The Hispano has equal brakes all round and therefore the rear brakes will be considerably lighter than ours. contd:- | ||