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).
Test report on battery ignition rubbing blocks.
| Identifier | ExFiles\Box 69\1\ scan0384 | |
| Date | 29th December 1924 | |
| X.4646. BATTERY IGNITION RUBBING BLOCK TESTS. Date. | Test No. | Material | Bench or Chassis. | Equiv. miles. | Wear | Remarks. 8.12.24. | 10 | Bone grey fibre. (2nd. samp) | 98-NK. | 14,800 | .007" | Run under severe chassis conditions in France. 15.12.24. | 11 | " | Bench | 10,000 | .004" | Cam unlubricated. 2UL 19.12.24. | 12 | Bone grey fibre. (1st. samp) | 9-PK | 10,000 | .007" max. | Run under severe conditions in France. 2.3.25. | 13 | Bone grey fibre. (2nd. samp) | Bench | 10,000 | .002" (max) | Cam lubricated. 2L 19.6.25. | 14 | Bone grey fibre. (1st. samp) | 6-GII | 12,239 | .004" (max) | Normal conditions on chassis. AS 30.6.25. | 15 | Bone grey fibre. (2nd. samp) | 5-EX. | 11,122 | .004" (max) | " 2D 17.6.25. | 16 | " | GF68. 8-GIII. | 10,090 | .012" | Normal conditions on chassis. 2E 17.6.25. | 18 | " | 93-NK | Considerably over 10,000 | .006" | Normal conditions on chassis. T2 29.12.24. | ||