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 a 20/25 HP chassis starter motor with Baldwin's stamped slotted plates.
| Identifier | ExFiles\Box 62\1\ scan0157 | |
| Date | 29th August 1933 | |
| 86012 By.{R.W. Bailey - Chief Engineer} From Hs{Lord Ernest Hives - Chair}/Wst. c. to By/RD. c. to E.{Mr Elliott - Chief Engineer} Hs{Lord Ernest Hives - Chair}/Wst.2/MA.29.8.33. 20/25 HP. CHASSIS STARTER MOTOR WITH BALDWIN'S STAMPED SLOTTED PLATES. We have now tested the first three of the 25 sets of the above motors now being assembled on production. It was found that these motors gave an inferior performance to the standard motors, as shewn on the attached curves, but at the load point where they are tested on production the difference is not of sufficient magnitude to warrant any alteration in the production test. The performance of these motors under the worst conditions however, i.e. near stalling point, is definitely worse, a reduction in the available stalling torque of approximately 10 lb. inches being measured. We attribute this reduction in stalling torque to the inferior permeability characteristics of the iron used and not to the use of stamped slotted plates. Apparently the iron used has a lower normal induction curve than "Lohys" and we recommend that further supplies should be of the "Lohys" quality. Hs{Lord Ernest Hives - Chair}/Wst. | ||