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).
The Phantom III Clutch, detailing methods to accommodate different clutch plate thicknesses.
Identifier | ExFiles\Box 129\1\ scan0252 | |
Date | 24th August 1937 | |
To By.{R.W. Bailey - Chief Engineer} 1110 also 312 Rm{William Robotham - Chief Engineer}/NRC.{N. R. Chandler}12/JH.24.8.37. Phantom III Clutch. With reference to allowance for the extra thickness, of the cushioned clutch plates, the position is somewhat complicated by the different thickness of plates, which are as follows :- (a) 100 on order from B. & B. have .125 Thermoid facings. (b) The 200 pairs of Thermoids on order from U.S. A.{Mr Adams} are .137. (c) With the By/RR plate being made experimentally there is an extra steel plate .022 thick. Three methods are possible :- 1. To fit a packing ring between the flywheel and the clutch cover. 2. To add metal to the face of the clutch cover. 3. To reduce the thickness of the pressure plate. With regard to replacements on customers cars, we suggest packing ring .070 thick is ample for Long B. & B. cushioned plates with either .125 or .137 facings. With regard to production the same could apply, although metal could be added to the face of this cover when existing stocks are exhausted. In order to use the clutch disc with the extra steel plate, the dimension should be increased to .100 which is the maximum dimension for a packing ring, on account of the depth of the spigot. In the event of adding metal to the face of the clutch cover, either the part number or a distinguishing mark should be added so that Depots may know that no packing ring need be fitted. Rm{William Robotham - Chief Engineer}/NRC.{N. R. Chandler} | ||