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 of crank and bearings to investigate alleged severe wear on chassis B.60.GA.
| Identifier | ExFiles\Box 146\3\ scan0150 | |
| Date | 30th October 1936 | |
| To Sr. c. to Hs.{Lord Ernest Hives - Chair} c. to E.{Mr Elliott - Chief Engineer} 8 1245 Rm{William Robotham - Chief Engineer}/Swdl.{Len H. Swindell}29/JH.30.10.36. Chassis B.60.GA. - Job No.35747. Paris Trials car alledged to have severe bearing wear. Re your memo. VA.2/ET.21.10.36. From the measurements which have been taken of the crank and bearings, there does not appear to be any undue wear either in the bearings or the crank. Allowing for working limits and taking maximum diameters of the main journals the maximum wear is .0005. On the minimum diameter the maximum wear is .0015 on the extent of ovality. The crank ins come inside the working limits and can be said to have no wear whatever. Regarding the main bearings the biggest wear registered on the maximum diameter is .0025, this on the rear main bearing. On the minimum diameter due to the bearings collapsing inwardly at the joint faces the biggest undersize measurement is .0025 this on Nos. 1.2 and 4 bearings. We cannot reconcile the measurement of No.6 intermediate main bearing which is said to have a gap of .007 in the case each side making .014 on the diameter and yet the actual internal dimensions of this bearing at this point is only .0005 undersize. It is our general experience that No.7, the rear main bearing is usually the worst with regard to hammering out, but in this particular case this bearing appears to be reasonably good and should not be causing any thumping or roughness. From the measurements, the big end bearings are in good condition the maximum wear being .00075. Fm/L.H.Swindall. | ||