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).
Casting tolerances and distortion issues for brake drums with cast-in backplates.
| Identifier | ExFiles\Box 120\1\ scan0284 | |
| Date | 5th March 1940 | |
| G.6/W. 1028 VS.{J. Vickers} 4/IA. 5.3.40. To:- Rm{William Robotham - Chief Engineer}/PJH. c.c. to Rm.{William Robotham - Chief Engineer} Brake Drums with Cast-in Backplates. In reply to your memo of 12.2.40, I should consider the limit of plus or minus .025 on the diameter of the sand castings not sufficient to cover what would be required, and would suggest that you increase this to at least plus or minus .050. With regard to the question of the distortion of the steel backplates after the casting operation, we regret that we have not details of the deviations which occurred with us at Glasgow, but no doubt if you get in touch with Mr.Knagg in the Iron Foundry he will be very pleased to supply you with full details of the experiments which took place at that time. I should imagine that you will find that the thinner backplates will distort to exactly the same extent as the thicker previous backplates used in our experiments. Handwritten: 0.025 distortion. Handwritten: VS.{J. Vickers} [signature] | ||