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).
Visit to Leyland Motors Ltd. detailing their use of magnesium castings and hardened crankshafts.
| Identifier | ExFiles\Box 128\1\ scan0151 | |
| Date | 26th September 1935 | |
| V 3531. To For. From Hs.{Lord Ernest Hives - Chair} [REDACTED] [REDACTED] [REDACTED] [REDACTED] RE. VISIT TO LEYLAND MOTORS LTD. Ud., RHO., and myself visited Leyland Motors. We were shown throughout the whole works and Experimental Departments. The points which I consider of interest to us were - (1) Magnesium Castings. - I was surprised to find that 80% of the light alloys used on the Leyland are Magnesium, including crankcase top and bottom half, covers, dashboard, etc. They pointed out that as they are taxed on weight they have to pay a lot of attention in getting rid of any unnecessary weight. They are making all their own Magnesium castings and are actually casting about six tons per week of magnesium. They have been helped by Sterling Metals. It was not, however, until they took the bold move of changing over to Magnesium in the foundry that they were able to overcome the practical difficulties. They estimate that a finished piece may be 10% more expensive in Magnesium than in Aluminium. They have found it necessary to separate the Magnesium from the Aluminium in the foundry because of the different treatment and sand which has to be used. Apart from our desire to use Magnesium on aero engines, I think there are a number of places on the motorcar on which we can use it and save weight. The saving of unnecessary weight is of importance to us. Take one instance, the present cast dashboard on the cars which is a heavy piece could be made in Magnesium. There are also a number of covers and unstressed parts on which there is very little risk. We ought also to develop Magnesium for the crankcase. It will be remembered that the 4 Litre Bentley had a Magnesium crankcase. It would appear that we shall not make the progress in the use of Magnesium until we carry out this work in our own Foundry. (2) Hardened Crankshafts. - They are using as standard case hardened crankshafts on all of their compression ignition engines. At the present time these number about 25 per week. They were forced to go to the hardened shaft in order to obtain satisfactory big end bearings. They went through a tremendous amount of trouble with the big end bearings on the Compression Ignition engine. They tried the Lead Bronze. They shewed us the plant which they use for producing the bearings, which was a similar scheme to our own except that they were quenching with water instead of oil. They obtained satisfactory results with Lead Bronze on big ends but found it very expensive. The ultimate solution they found for their big end troubles was | ||