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).
Procedure for bedding-in and testing leaf springs to eliminate squeaks.
| Identifier | ExFiles\Box 67a\2\ scan0235 | |
| Date | 26th October 1929 guessed | |
| - 2 - Procedure is as follows:- (1) Spring is built up without rebound clips, but with plates ground all over, polished etc. but not plated. (2) It is then put on the exercising rig and run for about 1/2 hour with plates wiped clean and not oiled. (3) Dismantled and "high spots" removed with a small grinding wheel - 60 Emery. (4) Reassembled and put back on rig with a slight film of oil between leaves. Run for 1/2 hour dismantled and inspected. Generally the high spots have disappeared, and a fairly smooth bedding is obtained. If not job is repeated. (5) On obtaining desired bedding, spring is tested for load and stiffness and marked. (6) It is then cleaned, cadmium plated and finally assembled. We do not know whether we have overcome spring squeaks by this method, but we have undoubtedly improved the springs, and have produced a bedding which will probably permit of good lubrication from the central chassis system by the method recently proposed by Mr. Hives, which we are trying experimentally. When the first pair of springs was put on this rig we found we could feel the plate-ends which were squeaking and feel the heat produced by the hard bedding at these points. On dismantling the plates these points showed as bright streaks about 1/8" wide and 3/8" long, surrounded by blue patches, and showing every mark of ripping and seizure. It does not appear difficult or expensive to eliminate these spots and produce a spring which will bed evenly somewhat as shown in A-14019 attached. Very truly yours, ROLLS ROYCE OF AMERICA, INC. Maurice Olley Encls: A-14019 SK-209 | ||