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).
Comparison of S.M.M.&T and R.R. standards for Dynamo Brush Design.
| Identifier | ExFiles\Box 60\1\ Scan122 | |
| Date | 18th September 1929 | |
| RR 238 (150 BKS.) (DB{Donald Bastow - Suspensions} 461-8-12 24) MP 306975 X8673 ROLLS-ROYCE LTD. INSTRUCTIONS. To E F C. Order No. PD 40. Customer's No. X 8673. Standardised Details of Dynamo Brush Design. Below are given the dimensions, etc, of a dynamo brush suitable for a machine of the RR 40/50 type; these dimensions having been adopted by the S.M.M.+T as standard for that particular class of brush. For comparison, a corresponding set of brush details, representing RR standards for the 40/50 dynamo brushes, are given. Detail | S.M.M.+T Standard. | R.R. Standard. --- | --- | --- Brush. | | Grade. | Electro-Graphitic | Electro-Graphitic Length. | 1.0" | 1.075" Width. | .875" | .498"x2 Thickness { Main | .375" | .280" Thickness { Control | .1875" | .187" Chamfer. | .040" | .031" Signed Cont'd.{John DeLooze - Company Secretary} This Sheet must be filed on completion of the work. | ||