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).
Design improvements for the rear cross tube, dumb-irons, and luggage grid.
| Identifier | ExFiles\Box 16\7\ Scan013 | |
| Date | 23th January 1927 | |
| To DA{Bernard Day - Chassis Design}/EV.{Ivan Evernden - coachwork} RG.{Mr Rowledge} HS.{Lord Ernest Hives - Chair} from R.{Sir Henry Royce} c. to BJ. Wor.{Arthur Wormald - General Works Manager} BY.{R.W. Bailey - Chief Engineer} X7400 EAC.7 LUGGAGE GRID AND X.7400 WHEEL AT REAR. X.7600 I quite agree that N.sch.2339 promises to be better than N.sch.2345. I am pleased we are doing away with the torsional dumb-iron. I should like to see the rear cross tube (i.e. the main one that becomes the cantilever for the shackle (spring)) more easily removeable, as I think in so many cases it will get damaged (bent) by people running into the rear. The dumb-irons could be unbolted, (or rivets cut off) from the frame, but would require to slide together on the tube. The stop for the spring shackles might possibly be forged on the dumb-iron, then possibly the dumb-irons could slide off the ends of the cross tube, which could then be repaired or replaced. I am not saying this is possible, or the best, but it may indicate an improvement. Our car here is quite an improvement in the above parts, both in appearance and utility. It may not be quite perfect. (Once the wheel worked its way up the face where bolted, and the hub knocked on the tube - luggage grid ) - just above the boss, and caused us to stop and examine. It seemed to be due to the elasticity of the tyre on the shoes, and the elasticity of the tubes supporting the face to which the wheel is attached). This latter flexibility does not exist on 20 HP. design. R.{Sir Henry Royce} | ||