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).
Measurements and condition of crankshaft components and Hall's Metal main bearings.
| Identifier | ExFiles\Box 146\2\ scan0066 | |
| Date | 7th September 1935 | |
| Sr/VA3/ET.I5.I.37 - 2 - Amount of bow at centre of shaft: .005". Diameter of : crank pins..: I"9985 : I"99825:I"9985:I"9985 : - Internal diameter of lead bronze big ends: 2.0015. HALL'S METAL MAIN BEARINGS: Amount of sinkage into: upper half of crankcase...: .005 : .OII : .009 : .OIO : .OIO : .008 : .OII Amount of sinkage into: bearing caps: .004 : .OIO : .OIO : .OIO : .OIO : .004 : .003 At the time of fitting the lead bronze bearings on the 7.9.35, the diameter of all the crankpins was I.9985" and the internal diameter of the lead bronze bearings was 2.0015". You will observe that no wear has taken place in these bearings during the 20.872 Kms. covered. The surface of these bearings is in an O.K. condition. We have trued up the journals of the crankshaft by hand. They were in a rather scored and poor condition. Upon examination of the liners of the lead bronze bearings, we found that the lead bronze on one liner had begun to detach itself from the steel portion of the liner. The remainder are intact. We have ordered in the usual way a set of liners in RR.56 material suitable for the big ends and, unless we hear from you to the contrary, we intend to replace all the existing liners of the big ends by the RR.56 type. We are returning the bearings to you for examination. Sr/VA.VA P.S. At the time we fitted the Hall's Metal bearings, we did not possess a Martell reamer. The bearings therefore had to be hand scraped, which is not an easy job with Hall's metal. | ||