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).
Technical memorandum discussing modifications and manufacturing options for the B.50 gearbox, specifically the reverse and first speed gears.
| Identifier | ExFiles\Box 112\2\ scan0086 | |
| Date | 6th February 1939 | |
| 6.2.39. B.50 GEARBOX. RHC{R. H. Coverley - Production Engineer}/Wld.1/FH.31.1.39. Reverse Gear. This has now been moved so that the clearance between this and overdrive is .815. The works do not know this but it does not alter the position except to make lapping easier. (1) The gear can be cut on a Sunderland rack by David Brown in a day. We have not got a rack. (2) It can be cut on any Maxicut by packing up the head with a block obtainable from Drummond. Humbers with a similar layshaft have all their Maxicuts packed up. Chassis side has one Maxicut and the Aero Shop several. (3) Necessary block and guides from Drummonds might take a month or two to get. First Speed. We agree this cannot be ground as a production job. If grinding shows itself to be necessary we can split the shaft or lengthen the box. Rm{William Robotham - Chief Engineer}/Gry.{Shadwell Grylls} P.S. A Sunderland rack in the Exp. would be very useful. It cuts any spiral angle without spiral guides etc. Hs{Lord Ernest Hives - Chair}/LS. says other machines more meriting of money to be spent. | ||