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).
Investigation of sample ebonite battery plate separators and discussion of new specifications with a supplier.
| Identifier | ExFiles\Box 54\5\ Scan018 | |
| Date | 10th June 1925 | |
| X4665 X.4414P. 10.6.25. The sample ebonite battery plate separators sent by Messrs. Peto & Radford have been investigated. The thinner sample representing standard is found to be .5 mm. (.020") and to contain 137 holes (.055 dia.) to the square inch. The thicker sample is found to be nearly 1 mm. (.037") thick and to contain 100 holes (.068 dia.) to the square inch. Contrary to anticipation, the thicker sample appears to contain 11% more hole area than the thinner sample. The representative from the New Eccles Rubber Co. has called, desiring to know what separators we desire. We have told him that we want a thickness of from .65 to .75 mm. perforated with 100 holes per square inch, like the thick sample. The New Eccles Rubber Co.'s representative stated that there would not be any extra cost in supplying Messrs. Peto & Radford with perforated ebonite separators to this specification. EFC. {E. Fowler Clarke - Electrical Engineer} 1mm = .040" .5mm = .020" ✓ 100 x d₁² = .463 ✓ 137 x d₂² = .415 | ||