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).
Agreed-upon methods and materials for vehicle noise insulation.
| Identifier | ExFiles\Box 138\1\ scan0122 | |
| Date | 27th February 1935 | |
| 2634 R Wyman Noted [Signature] To Sg.{Arthur F. Sidgreaves - MD} and Wer. from E.{Mr Elliott - Chief Engineer} c. Hs.{Lord Ernest Hives - Chair} Ey. Mx.{John H Maddocks - Chief Proving Officer} La.{L. A. Archer} Da.{Bernard Day - Chassis Design} EV.{Ivan Evernden - coachwork} re Noise Insulation. It was agreed at the last conference with Sg.{Arthur F. Sidgreaves - MD} in Derby that No.3. SpectreCodename for Phantom III should be earmarked to be fitted with an insulated dash in place of the double dash with air ventilation, with which No.2. SpectreCodename for Phantom III is equipped. We also propose to incorporate all the other features for the retention of noise which have now undergone a satisfactory preliminary test on No.1. Bentley. In general it can be stated:- (a) that all floorboards must be provided with lap joints bedded on felt or some other suitable soft material and screwed down securely in a sufficient number of places. (b) all footboard and surfaces should be covered with a layer of felt of 1/2" thick attached by adhesive to rubber sheet .062" thick. This combination is much lighter than using sorbo matting. In the case of sunken foot wells and heel boards, these must be lined with felt and covered with matting and where exposed to damp from the passengers boots and shoes the felt should also have the protection of the rubber sheeting to prevent it from taking up moisture. (c) The space underneath the rear seat should be filled in with a sheet metal shield coated with 1/4" thick felt on the top side. At the moment the experimental one is made of 18 gauge steel, and is separate from the seat tray. We propose to use the same gauge of aluminium with a light framing of wood for carrying the cushion rail and avoiding a separate seat tray. (d) The dashboard must be insulated with 1/2" felt re-enforced on the outside by a layer of some material such | ||