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).
Causes of obsolete road springs and production procedures for new ones.
| Identifier | ExFiles\Box 154a\4\ scan0030 | |
| Date | 1st January 1937 | |
| Rm.{William Robotham - Chief Engineer} RHC.{R. H. Coverley - Production Engineer} Hs.{Lord Ernest Hives - Chair} BY.5/G.1.1.37. GRY{Shadwell Grylls} ? LES ? ROAD SPRINGS Referring to Rm.{William Robotham - Chief Engineer}1/AP.15.12.36. and Rm{William Robotham - Chief Engineer}/Les.2/AP.15.12.36. there are certain points which must not go unchallenged in the above memos. (1). Reduction of Obsolete Springs. Not one of the suggestions affect this aspect of the matter in the slightest. Obsolete springs are due to two causes :- (a). Change of designs in many cases called for by Experimental Department, such as the large eye to Phantom 111 rear spring and alteration to rating. These changes are the real cause of obsolete springs. (b). Again for Phantom 11, Bentley and Phantom 111, the series of poundages given by the Experimental Department have been too low and have had to be increased. (c). Weights of Chassis and bodies increasing, mainly the latter - these are only few in number, and in time are absorbed by open bodies or specially light bodies due to special body work being occasionally called for. (2). Production procedure. I cannot agree this is affected, we order three poundages and the makers aim at these three poundages, but their results are not ± 15 lbs. they are ± 24 on the lighter types and ± 49 on the heavier. We do not specify when ordering a series of springs fine differences in poundages, as is inferred, and therefore Firths are not struggling with a long list of slightly variant poundages for the same general type of spring. I am certain Firths cannot work to ± 15 as suggested, but have asked them why they say they can do this, and yet at the same time supply springs which vary so widely from the spring poundages we specify, their variations are as much as 45 lbs. above and below the figure called for in different deliveries. | ||