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).
Comparison between suppliers Gabriels and Jessops for the production of castings, detailing delivery times and material properties.
| Identifier | ExFiles\Box 142\4\ scan0084 | |
| Date | 13th August 1937 | |
| - 3 - HPS.{Horace Percy Smith - Experimental Factory Mgr}4/VS.{J. Vickers}13.8.37. the production of experimental pieces, they appear disinclined to undertake the manufacture of such castings on a production basis, and cannot promise reasonable deliveries. Gabriels, on the other hand, are very anxious to accept our work, whether on an experimental or production basis, and although their methods are somewhat rough and ready, they promise four weeks delivery on the various castings we have so far asked them to produce, as against eight weeks from Jessops. Therefore, since time is the chief consideration, on Bentley III at any rate, Gabriels have been used to produce the various brackets used in connection with the front suspension mechanism in addition to the levers already mentioned, but we have asked Jessops to produce one or two Phantom details, which are not so urgently required, in order to provide an opportunity of comparing the general standard of quality of castings supplied by these two firms respectively. According to Mr. Topham, Works Manager, the material Jessops propose to employ would have the following physical properties :- Maximum Stress 35-40 tons/sq.in. Yield Point. 20 tons/sq.in. Elongation (min.) 15%. Minimum Bend. 60°. This material should, therefore, be much more suitable to our purpose than the material used by Gabriels, which is merely the equivalent of a commercial quality mild steel. Furthermore, since their high frequency furnace will be employed for any castings we may ask them to produce, they should be well able to control the quality and consistency of material, which is a decided advantage where stressed pieces are concerned. HPS.{Horace Percy Smith - Experimental Factory Mgr} | ||