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).
Tests of contact breaker rubbing block material, with a focus on Bone Grey Fibre.
| Identifier | WestWitteringFiles\N\July1925-September1925\ Scan3 | |
| Date | 1st July 1925 | |
| To R & E.{Mr Elliott - Chief Engineer} from EFC. c. CJ. & PN.{Mr Northey} c. Da.{Bernard Day - Chassis Design} By.{R.W. Bailey - Chief Engineer} c. Wor.{Arthur Wormald - General Works Manager} Rg.{Mr Rowledge} c. Wd.{Mr Wood/Mr Whitehead} EFC3/T1.7.25. ORIGINAL X.4646 - TESTS OF CONTACT BREAKER RUBBING BLOCK MATERIAL - AND IN PARTICULAR OF BONE GREY FIBRE. The up to the present standard meterial for the battery ignition contact breaker rubbing blocks has been and is continental hakelite, arranged with the fibres at right angles to the rubbing surface. This material is reasonably satisfactory though the wear in some circumstances has been appreciable. Some time ago we were informed by our Mr. Olley that American fibre known as Bone Grey, the first word referrieng to hardness, and the second to colour, was the material they had found best for contact breaker rubbing blocks. Accordingly we obtained two samples, one which we call the first sample, from the Diamond Fibre Co. and called by them 'Whalebone fibre', and another which we call the second sample from our own people in U.S.A. Apparently there would be no difficulty as regards the supply of this material. Contd. | ||