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).
Notes on the practical forging techniques for various metals.
| Identifier | ExFiles\Box 109\3\ scan0003 | |
| Date | 21th November 1939 | |
| MYTH 700 E Bn.{W.O. Bentley / Mr Barrington} Da.{Bernard Day - Chassis Design} COPY. HPS{Horace Percy Smith - Experimental Factory Mgr}/Cy.1/BA.21.11.39. NOTES ON FORGINGS. ------------ The following remarks are intended to give Design and Detail Draughtsmen a brief outline of practical forging technique applied to our various products in steel, brass, and aluminium, the normal errors to be expected and the various pit falls to be avoided in design and also the reasons for the various features which arise. Types of Tools used in making forgings. Steel and Aluminium forgings are. usually made in dies operated in Drop Stamps or Hammers, or forging machines. Forging machines, hydraulically operated, are used for upsetting flanges or collars on shafts, for producing hollow work, such as shafts and gears, and improving grain flow. Hot brass forgings are also made in Drop Stamps, but more frequently in Screw or toggle operated presses, particularly in regard to hollow work when two, three or four part dies are used. These complicated brass pressings are remarkably clean and accurate, but unfortunately can only be produced in soft brass, such as "Dixtampo", a very easy flowing material, which is, however, totally unsuitable where any wear resisting properties are required. Other wear resisting alloys, such as "Carobronze" can of course be forged, but not with the same facility as "Dixtampo". The oil toughened steel dies for drop stamps are made in pairs usually with an equal impression in each die, or when a flat face is required on one side, the whole impression is made in the top die. The face of each die is recessed to take the surplus metal from the forgings. To make the following remarks clear in regard to sizes, we are referring of course to our own products, and a small lever would be from 1½" to 3½" in length, weighing from 2 - 3 ozs., a medium lever 3½" to 6" long weighing 3 - 8 ozs., and a larger lever 6" to 1" weighing 8 ozs. to 3 lbs., or similar type of forging up to Con. Rod size weighing 7 to 8 lbs. | ||