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).
The performance of a type of brush, noting wear, dust, surface condition, noise, and commutation qualities.
| Identifier | ExFiles\Box 60\1\ Scan032 | |
| Date | 8th December 1924 | |
| RR 23B (150 BKS.) (DB{Donald Bastow - Suspensions} 461-8-12 24) MP 306975 ROLLS-ROYCE LTD. INSTRUCTIONS. To__________________________________________________________19__ Order No. PD 8 (2) Customer's No.___________________ This is more than the wear of corresponding brushes in the standard grade, and consequently the brush dust deposited on the end bracket was more. A slight increase in wear was anticipated, but it was thought this would be justified by improved silence and commutation qualities. The brush surfaces were in very good condition; the positives being only slightly blackened along the trailing edges, and the control brushes dull along the trailing edges, while the negatives were almost entirely polished. Some sparking had been observed at all the brushes, particularly at the higher speeds. The commutator segments were blackened along the trailing edges. In respect of both chattering and shrieking noises the brushes were an improvement. Generally, this type of brush appears promising, and is worth further testing on a car to decide its wearing and commutation qualities. Signed C.A.P. This Sheet must be filed on completion of the work. | ||