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).
Secret memo discussing issues and improvements for a relay advance and a four-speed gearbox.
| Identifier | ExFiles\Box 6\4\ 04-page045 | |
| Date | 3rd February 1925 | |
| To E.{Mr Elliott - Chief Engineer} DA.{Bernard Day - Chassis Design} AJS. from R.{Sir Henry Royce} SECRET. R1/M3.2.25. c. to CJ. BJ. Wor.{Arthur Wormald - General Works Manager} c. to EB. He. BY.{R.W. Bailey - Chief Engineer} E.{Mr Elliott - Chief Engineer} A.{Mr Adams} C. U. S. A.{Mr Adams} X.8555 X.5310 RE. RELAY ADVANCE, AND FOUR SPEED BOX. Below you will see copy of telegram sent to Derby :- ROYCAR. DERBY. BAILEY. NOTHING SERIOUS WRONG WITH RELAY ADVANCE IF TESTERS ADOPT PROPER GAUZE AND CLEARANCES AND WITH FOUR SPEED BOX IF SLIDERS HAVE AMPLE CLEARANCE. BUT IF ANY OF US HAVE SUGGESTED IMPROVEMENTS AS LARGER DIA. PINIONS OR SHAFTS EMBODY IF CONVENIENTLY POSSIBLE. ROYCE". and I have written to Mr. Johnson somewhat similarly pointing out that the reports of faults in the above should not cause a change of policy, as I think it is only for the tests to find the correct requirements. As regards the relay, I have concluded that with reasonable gauze say .100 per inch and reasonable clearance its reliability is satisfactory. If however the sleeve magneto is very heavy to control let us use some other - Watford, or good make. We still ought to be better than Scintilla. I suggest that it is worth considering a machine with sleeve for hand control and relative cam movement for auto control. Also for starting when battery is down a hand magneto might be worth installing. E.{Mr Elliott - Chief Engineer} will look into Hs.{Lord Ernest Hives - Chair} suggestions of bigger joints or perhaps ball joints so that they can be adjusted if worn. It is still left for a committee of Design & Production to decide what is best to offer sales. It depends upon more things than I have before me, and I have given my requirements especially of reliability and synchronism. ----------------- Regarding the troublewith four speed box, the little information I have at the moment makes me come to the following conclusion :- The slider forks were fitted with insufficient clearance, and naturally being somewhat out of square with the collars, wriggled the sliding pinions about on the microscopically slack shaft and caused the epicyclic creep I feared came from the tooth pressure. Then Hs.{Lord Ernest Hives - Chair} ordered the gears to be wedged into gear, which was done unwisely so as to cause unnecessarily heavy collar friction and heat, resulting in a disastrous looking job. Really one feels that no other alteration but another .010" clearance in the forks is needed, perhaps making a total of .020". Also you will remember how I asked for a good clearance between the end of the change speed lever and the lugs on the slider as I think this and want of accurate timing is the cause of the lever not sliding freely sideways. Compare contd :- | ||