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).
10,000-mile test of a 28-slot armature, detailing brush wear.
| Identifier | WestWitteringFiles\S\September1928-October1928\ Scan078 | |
| Date | 19th September 1928 | |
| RR 238 (150 BKS.) (DB{Donald Bastow - Suspensions} 431-8.12 24) MP 306975 X.8672 ROLLS-ROYCE LTD. INSTRUCTIONS. To: E.F.C. Order No. PD 30. Customer's No. X 8672 10,000 Miles Test of 28 Slot Armature. The 10,000 miles test of the 28 slot type of armature was commenced 22-3-28 on 12 EX. No 3 armature was run in the carcass of K machine, the complete dynamo being otherwise standard. The dynamo was set to give the maximum permissible output, and was run in conjunction with green-lamp switch G.{Mr Griffiths - Chief Accountant / Mr Gnapp} Commencing with a clean commutator, well bedded brushes etc., the various points with respect to commutation together with brush wear, observed at the end of the test, were as follows:- Brush wear. | | Positive | Negative | Control | |---|---|---|---| | Inner. | .006" | .005" | .007" | | Outer. | .006" | .009" | .009" | Cont'd.{John DeLooze - Company Secretary} Signed This Sheet must be filed on completion of the work. | ||