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).
Visit to Elliott Bros. to discuss improvements and quality issues with their ammeter.
| Identifier | ExFiles\Box 168\5\ img109 | |
| Date | 11th May 1927 | |
| By.{R.W. Bailey - Chief Engineer} from WD.{Mr Wood/Mr Whitehead} c. to EFC. Wd{Mr Wood/Mr Whitehead}7/NJ11.5.27 Elliott Ammeter - X.4622. The remarks conveyed in EFC1/T2.5.27. By9/H6.5.27 and EPC3/T9.5.27 were communicated by letter to Elliott Bros.(London) Ltd. and yesterday I went to their Works at Lewisham and discussed the several matters with them. At the request of Elliott Bros. I handed them one of our standard Weston Ammeters and this was fixed alongside one of their (Elliott's) ammeters in a cardboard holder and the two together tested for the electrostatic effect produced by rubbing the glasses. Owing perhaps to the fact that the atmosphere was somewhat humid, the rubbing of the glasses with a chamois leather had very little effect; the Weston instrument being the first to show any effect - the ultimate deflection being the same in both instruments. At Elliott's request I left with them the Weston instrument and they will carry out further comparative tests and forward report the results. Elliotts have made a series of tests with various distances between the glass and the dial and have found that this does not affect the result unless the distance from glass to dial is far greater than that in the Weston instrument. The suggestion that slightly conductive glass should be used instead of highly insulating glass is impracticable, as conductive glass is not now obtainable. With regard to the securing of the glass, Elliotts explained that their use of an internal bezel secured by cement was prompted by the knowledge that occasionally glasses are broken in transit and while the instrument is in use, and the cemented internal bezel would allow of a new glass being fitted without destroying the case. However, as we desire a more permanent fixing, they will follow the practice of the Weston Co. and pin the internal bezel to the case. They point out, however, that this method entails the supply of a new case and internal bezel if a glass for any reason has to be replaced. I impressed upon all the departmental Managers at Elliott Bros' factory the necessity of every instrument they supply to us being 100% quality and finish, adding that if they could not produce an instrument equal to the Weston at the price they were now charging us, they must say so frankly and state how much extra they must have to enable them to supply what we want. I think some good may come of my visit and I have undertaken to go to Lewisham again should occasion arise. (contd) | ||