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).
Engine bore treatments, including chrome plating, and the comparative effects of different piston types on bore wear.
| Identifier | ExFiles\Box 132\5\ scan0057 | |
| Date | 11th March 1939 | |
| -5- Rm{William Robotham - Chief Engineer}/CTS.{C. Trot Salt - Carburation}3/MH.{M. Huckerby}11.3.39. the various experimental materials already mentioned, and testing them against the "Brico". CHROME PLATING. Another method of treating the top of the bores is to Chrome plate. To quote one firm who have been experimenting with the process for about 2 years; this firm is Rovers. Up till quite recently they had been plating the complete length of the bore, and could not get over piston scuffing troubles. They went to a lot of trouble trying various makes of piston, and it would seem likely that trouble would be experienced in efficiently lubricating a very smooth finished hard bore. They then took the cue from the short insert, and confined their plating to the same proportion at the top of the bore. We have seen their tackle for doing this job, and Aspley's report explains the process in detail. It seems that Rovers are having quite a measure of success with Chrome plated bores, they actually quoted minute wear on individual mileage cars having covered as much as 90,000 miles. EJJ has been instructed to make drawings for suitable tackle in co-operation with Aspley. PISTONS. It has been stated in a previous report that the difference between the R.R. split skirt piston and the solid skirt Aerolite affects bore wear to the extent of the split piston causing one third less wear than the solid skirt. This is based on the fact that bore wear increased by this amount between series DK and EF, when the Aerolite was introduced on the 3½ litre Bentley. The figures for the Bentley, shown at the beginning of this report, agree with this statement and the figures were obtained independently. | ||