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 from a supplier discussing the specifications and delivery of special front springs.
| Identifier | ExFiles\Box 87\4\ scan0049 | |
| Date | 6th February 1935 | |
| THOS. FIRTH & JOHN BROWN LTD. INCORPORATING THE WHOLE OF THE UNDERTAKING OF THOS. FIRTH & SONS LTD AND THE STEEL BUSINESS PREVIOUSLY CARRIED ON BY JOHN BROWN & CO LTD ATLAS & NORFOLK WORKS SHEFFIELD.1 Telephones: ATLAS & NORFOLK WORKS SHEFFIELD 20081 (11 LINES) TINSLEY WORKS @HEFFIELD 41193 SCUNTHORPE FOUNDRY SCUNTHORPE LINCS 22 Telegraphic Addresses: FIRTH SHEFFIELD ATLAS SHEFFIELD London Office: 8, THE SANCTUARY WESTMINSTER, S.W.1 Telegraphic Addresses: MESMERIC, PARL, LONDON ALDWARKE, PARL, LONDON Telephone Number: 8310 VICTORIA Codes: PRIVATE A.B.C. 6TH EDITION, BENTLEY'S 1912 & 1929, LIEBER'S, LOMBARD, MARCONI, WESTERN UNION 5 LETTER. REGISTERED OFFICE: ATLAS WORKS, SHEFFIELD YOUR REFERENCE EXPT/L.Dept. HS{Lord Ernest Hives - Chair}/Les.24/KW. OUR REFERENCE WHICH PLEASE QUOTE Spring Dept, Tinsley. HWP/3/35. 6th.February. 1935. Messrs.Rolls-Royce Ltd., Nightingale Road, DERBY. Dear Sirs, 2.Special Front Springs. Your order No.76760, - dated 21.1.35. We are forwarding on Saturday next, 9th inst., the 2.- 1200 lbs Springs to the above order. You, of course, appreciate that the range of stress of these Springs is exceptionally high viz. with 10" deflection to the loaded position it is 43.6 tons per square inch and to the Maximum Bump position of 14" is 61.1. tons per square inch - figures which are 30% and 20% higher, respectively, than your highly stressed 20/25.h.p. Standard low-rated Front Spring F.58602; also 50% and 31% higher, respectively, than your Standard 40/50.h.p. Front Spring F.83311, in which the deflection for the same loading is 4 1/2". Owing to the limitations imposed by your requirements, we decided to make the Mainplate .17" thick, - 2nd. plate .16" thick, 8. plates .15" thick, and the remaining 7. plates .14" thick, making a total thickness of 2.51". We have lubricated the Springs throughout and fitted 6 - Clips to each Spring as such were thought necessary in view of the very thin Mainplate employed. The finished weight of each Special Spring is 42.lbs, and your Standard 1200.lbs spring is 43.lbs. We trust these Springs will be found suitable for your purpose. Naturally, we do not look upon Springs of such a design as being normal for any type of suspension springs for road vehicles. Yours faithfully, THOS.FIRTH & JOHN BROWN, LTD. H.W. Pooles for Director. | ||