List of cost reduction suggestions for the Wraith Clutch, including material changes and machining modifications.
| Identifier | ExFiles\Box 8\1\ 01-page35 | |
| Date | 25th February 1937 | |
| SECRET 612 Smith C.S. Des. Res. Rem. HPE E {Mr Elliott - Chief Engineer} /HDY. {William Hardy} 3/HP.25.2.37 Wraith Clutch. The following suggestions have been made (see E {Mr Elliott - Chief Engineer} /FSN.3/MN.18.2.37) to reduce cost:- (1) Carrier for release bearing GB.2091 to be of cast iron instead of 5% nickel steel. (2) Trunnion blocks GB.2086 to be of cast iron. (3) The thrust pad GB.2086 to be made in cast iron with a chilled face for the pressure plate levers. (4) Machining on the clutch operating shaft not necessary for a bearing surface should be deleted (We have already instructed this on N.Sch.4676, but in this case the machining was to be deleted when new dies were made). With the present forging G.65364 this results in an increase of weight of .750 lbs. However it is now agreed that this is to apply whether new dies are made or not, but in the event of new dies being made the shaft diameter reverts to the present machined size, as shown by N.Sch.4676. We are not in agreement with the suggestion by E {Mr Elliott - Chief Engineer} /Fsn. to delete the plug in the middle of the bore of the shaft, but an economy can be made by drilling the shaft .625 diameter an equal distance from each end, so as to leave a short length solid which is then drilled .1875 dia. The length of the solid section may be such that the length of the .1875 hole is approximately .2". E {Mr Elliott - Chief Engineer} /HDY. {William Hardy} | ||
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).