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).
Process and results of coating switches and miniature holders for a lighting installation.
| Identifier | ExFiles\Box 38\6\ Scan168 | |
| Date | 22th February 1919 | |
| R.R. 235a (500 T) (S.D. 408. 26-4-17.) Bm. 2/156/13. X.3424 EFC. February 22nd, 1919. H13/EB22219. Laboratory. Re X.3362 - LIGHTING INSTALLATION FOR W.W. X 3424. I have coated 5 switches which had not been treated before, and return them with this. The 3 miniture holders are also sent, but the switches that had been previously coated will not be very satisfactory if re-done, since the removal of the original coat will tend to make the covers thin and make the surface rather irregular; for this reason I am sending these 5 switches back as they were. In my note H13/EB11219, I stated that the Shellac varnish should not be on the surface covers etc, sent in for coating since it interferes with the process, and we have to remove it before applying same, further I made a note that it would be better to start with a matte surface on the brass, since this would give a matte appearance finally after coating. I should like your re-marks with repect to these points. We have another method which gives rather a darker coat but this employs arsenic & for this reason is not so suitable for works production. If desired however, we can do you some Switches by this method. WCH | ||