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).
Suitability and issues with different bonnet locks, comparing the Vaughan lock to a bar-type lock for P.2. chassis.
| Identifier | ExFiles\Box 25\1\ Scan121 | |
| Date | 19th January 1932 | |
| Y 1140. Cx.{Major Len W. Cox - Advertising Manager} From Hs{Lord Ernest Hives - Chair}/Les.{Ivan A. Leslie} c. to Wor.{Arthur Wormald - General Works Manager} Da.{Bernard Day - Chassis Design} c. to By.{R.W. Bailey - Chief Engineer} S. Hs{Lord Ernest Hives - Chair}/Les.5/MA.19. 1. 32. K7260 BONNET LOCKS P.2. In reply to Cx{Major Len W. Cox - Advertising Manager}15/KW.15.1.32. Diamond engine mounting necessitates a centre radiator mounting. In order to benefit by this centre radiator mounting it is necessary to allow for relative movement between the bonnet and the frame. Our bonnet clips are satisfactory, because they are spring operated, the spring taking up the bonnet to frame movement. The Vaughan locks as now fitted on production are not suitable for this movement. The alternative lock is R's bar type lock. This type is obviously better for our requirements. The cost of the bar lock is £2. 9. 6d and the present Vaughan lock is £1. 7. 10d. This means an increase of £1. 1. 8d. These modified figures have only been completed this week. With reference to PN{Mr Northey}'s recent complaint in which the Vaughan lock had worn the bonnet strip on 5 cars at Lillie Hall in his memos PN.{Mr Northey}17/VT.23.11.31. and PN.{Mr Northey}4/VT.24.11.31. The bar lock overcomes this common fault. Without bonnet locks P.2. bonnet is easy to close. The Vaughan lock makes this distinctly difficult. No such disadvantage is experienced with the bar type locks. We note that you say that S.G. has found no disadvantage using the Vaughan lock with diamond engine mounting on 56-GN. We however understand that Sg.{Arthur F. Sidgreaves - MD} has previously complained of the near side of bonnet oscillating at the radiator. When 56-GN was last at the works for diamond engine mounting to be fitted we noticed this oscillation. To overcome it we were obliged to fit new bonnet strips. This bonnet had been continually shut with the locks outside the bonnet strips. The locks had worn its way right through the bonnet strips. We have chamfered the new bonnet strips and locks to enable the bonnet to close correctly more easily, but were not satisfied with what we imagined to be a temporary cure. Bar locks would have been much more satisfactory with this car. Although bonnet locks are not included in standard production, we feel that a customer who is ready to pay for bonnet locks should have the type suitable for his car. Out of 50 P.2. chassis dispatched since bonnet locks are not standard production, 21 chassis have had bonnet locks fitted. Hs{Lord Ernest Hives - Chair}/J.A.Leslie. | ||