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).
Letter to The Adamant Engineering Co. discussing failures in steering cams and proposing changes to the case hardening process.
| Identifier | ExFiles\Box 153\4\ scan0104 | |
| Date | 18th June 1941 | |
| Task 1300 18th June, 1941. Rm{William Robotham - Chief Engineer}/PJH.1/EH. Commdr. F.G. Matravers, Messrs. The Adamant Engineering Co., Ltd., Dallow Road, LUTON. Dear Commdr. Matravers, We thank you for your letter of the 11th. instant concerning our steering cams. In view of the fact that the two cams which have failed were given your standard heat treatment, there seems to be little doubt that the failures were caused by the relatively high front axle weights combined with large section tyres. We are naturally anxious to avoid having to increase the size of the steering gear for the two models of car involved, as this would necessitate our having two types of gear in production. We have found that increasing the depth of case on the rollers from a possible minimum of 0.032 to a minimum of 0.050 after grinding, has greatly increased their load capacity. So far as we can see, the same effect should apply to the cams. Since the cams are not carburised in the bore a case of 0.050 - 0.060 on the outside would not result in dangerously thin cores in heavily loaded regions. As a last resource before we redesign our system to incorporate a larger gear, we would like to try the effect of a deeper case. If you could make for us two cams to your M.22313, one with your standard low limit case of 0.031 on unground surfaces, and one with 0.050 on these surfaces, we could arrange to do an accelerated comparative test to determine how much the change is worth. Will you please let us know whether you could do this for us. We could probably supply the necessary material if this would be of any help. Yours faithfully, | ||