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).
Revision of the 20 HP crankcase design due to complications with foundry work.
| Identifier | WestWitteringFiles\C\September1919\ Scan1 | |
| Date | 9th September 1919 | |
| To Pts from E.{Mr Elliott - Chief Engineer} (Strikethrough) Copy to Gd. (Strikethrough) " BN.{W.O. Bentley / Mr Barrington} (Strikethrough) " EH. (Strikethrough) " EPC. ORIGINAL. X.3536 RE 20 H.P. CRANKCASE. It has been found necessary to somewhat revise the 20 H.P. Crankcase. You will recollect that the crankcase as drawn was to have transverse cells opposite the front and rear main bearings. These are found to cause much complication in the coring, and they do not promise to make foundry work very simple as regards ventilation of cores etc. We are therefore actually proceeding with the crankcase on the lines somewhat of the 40/50 H.P., in which the front and rear bearings are carried on single webs like all the other bearings, and the arms are boxed, one web of the box coinciding with the web of the main bearing. This allows the wheelcase complete as designed, to be brought nearer to No.1 cylinder, thus making the engine shorter and lighter. It requires a certain amount of modification to the wheelcase casting. I send you this foreword so that you can arrange a suitable policy. We shall send you the drawings on which we are now engaged, at the earliest possible moment. E.{Mr Elliott - Chief Engineer} STAMP: RECEIVED 9 SEP 1919 | ||