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).
Material and application method for harness cable varnish.
| Identifier | ExFiles\Box 61\1\ scan0154 | |
| Date | 26th February 1931 | |
| To Mr Neill: I believe this is the information you want for Rolls-Royce. SdE. X 6011 To:- Dr. E.O. Turner. From:- NAN/P. 26th February 1931. HARNESS CABLE VARNISH. Material used. After consulatlon with the cable manufacturers it was decided that a cellulose varnish would make a suitable protection and finish for cable harness. Several samples of cellulose varnish were supplied to us and subjected to various tests. The varnish most suited for this purpose was Black [strikethrough]Celalose[/strikethrough] varnish, SM.37.L, supplied by The British Celanese Co., Derby. This varnish gives a smooth finish and is not appreciably softened by petrol or mineral oil. Method of Application. It is understood that the method of application in the case of plain braided cables is as follows. The cable is passed at a definite rate into a bath of the varnish and out through rubber rings or other devices to remove excess of fluid. By allowing sufficient distance between the successive baths it can be arranged that each coat is sufficiently dried by passage through the air. Three or four coats of varnish are necessary to obtain a smooth finish. In the case of harness with branches, it was found impossible to apply the varnish by dipping, and application by brushing was resorted to. The first coat was thinned down somewhat with the appropriate solvent mixture in order to increase the penetration of the varnish into the fabric. Each coat dried in about 15 minutes. nan | ||