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).
List of proposed design alterations for engine components with accompanying sketches.
| Identifier | WestWitteringFiles\N\October1925-December1925\ Scan105 | |
| Date | 21th November 1925 guessed | |
| (2) (12) Cancel the cast aluminium tube and flanges surrounding the oil pump drive in the lower half crankcase. (13) Cancel the top and bottom cored holes in the front feet of crankcase and knock out the wall shutting out the front feet cavities, except for sufficient depth of web to carry the joint across for the lower half. This alteration does not remove a great deal of material but it simplifies the casting, replacing 3 cores with 1., and thereby makes it more possible to hold the thickness of the walls nearer the correct dimension. This applies generally to the proposals to simplify the crankcase. (14) Replace the bolts at present securing the cyls. and heads to the crankcase by studs. The objection to the studs, namely, that they tend to screw out when the head is removed, is to be overcome by providing them with squared collars which engage squared holes in the cyl. block, and are thereby locked - see sketches:- [Text from sketch 1] CYLINDER BLOCK WITH LARGE CLEARANCE HOLE DRILLED FROM ABOVE FOR BROACHING SQUARE. SQ WITH CORNERS REMOVED MILLED FROM ROUND COLLAR THRD SAME DIA AS UPPER END OF STUD BUT 3 OR 4 DIAS DEEP IN CRANKCASE This alteration saves considerable weight in the crankchamber by considerably reducing the length of the bosses required for these studs. It also saves the drilling of about 120 small holes which we have at present to do on the existing design. (15) Make top valve gear cover from an aluminium sheet metal pressing with suitable sheet metal angles rivetted on to form a flange - see sketch. [Text from sketch 2] JOIN IN THESE ANGLES TO COME HALF WAY ACROSS AT EACH END. | ||