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 Thos. Firth & Sons regarding proposals and modifications for 20 HP Front Springs.
| Identifier | ExFiles\Box 106\1\ scan0007 | |
| Date | 16th February 1925 | |
| COPY. THOS. FIRTH & SONS, LIMITED. NORFOLK WORKS, SHEFFIELD. MMF/EFS. In your reply please quote STEEL DEPT. 16th, February 1925. Messrs. Rolls-Royce Ltd. Nightingale Road, Derby. Dear Sirs, 20 HP. Front Springs F.53332. We enclose herewith a table giving the details of thicknesses and lengths which we propose for the new springs you are requiring. You will notice that we suggest that the three poundages namely, 550, 600, and 650 lbs, which you have at present called for, should consist of nine plates. As regards the main plates, we again propose to adopt a compound curve for these plates before assembling, as on the 43¼" 40/50 HP. Front Springs. On arriving at the dimensions suggested on this table, the actual stressing of the plates has been kept comparatively low, and they should obtain results comparable with those given by the later type of 43¼" 40/50 HP. Front Springs. We have submitted the modifications in the manufacture of the clip plates to Messrs. Woodhead's and will forward their reply as soon as received. In the meantime we are sending them material from which to form the main plates. Yours faithfully, THOS. FIRTH & SONS, LIMITED. (Signed) Mark Firth. for Director. P.S. We note that Drawing F.53332 gives no radius in the neck of the main blade, but now that we suggest the thickness of .25" for this blade, perhaps you can give the necessary information. | ||