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).
Design review and critique of a Japan 3 petrol tank, with suggestions for modifications.
| Identifier | ExFiles\Box 106\2\ scan0053 | |
| Date | 29th January 1931 | |
| DA{Bernard Day - Chassis Design}/EV.{Ivan Evernden - coachwork} E.{Mr Elliott - Chief Engineer}) FROM R.{Sir Henry Royce} BY.{R.W. Bailey - Chief Engineer} HS.{Lord Ernest Hives - Chair}) (At Le CanadelHenry Royce's French residence.) C. to SG.{Arthur F. Sidgreaves - MD} WOR.{Arthur Wormald - General Works Manager} HY.{Tom Haldenby - Plant Engineer} RHC.{R. H. Coverley - Production Engineer} XS460 R2/M29.1.31. JAPAN 3. PETROL TANK. This looks rather a lot of work but I suppose it compares favourably with competitors in cost value. (1) It seems to me that it is unimportant that the ends of the filter tubes are cut off at an angle: it is more costly, & requiring some care to place the right way round. (2) The filter appears unnecessarily large in dia. and I fear as a casting in brass it will be very heavy, and also require much hand finishing. I should vote for a cast brass bend, piece of thin tube, and a die cast top, which ought to be nearly finished as it leaves the dies. we must reduce the weight and cost. There is some error in "steel casting" as alternative. I fear it would be of no use. BODY SHEET. The single piece with folded joints sounds preferable to pressed in two halves and welded. Anything that can be reduced in size and weight appears to reduce cost. The tube right through is good: I believe it was originally, then made in two halves to allow central float of gauge which is now not used. I suppose filler cap should be petrol tight to prevent spilling at corners. I should like to see detail of this worked out to some perfection suitable for assembly only. Perhaps with spring loaded cover toggle not needed: hook catch might be less expensive and less pieces, and more lastingly robust, but perhaps toggle better to handle. One would think it possible to make the Sprengal pump for the petrol gauge the same angles as the filters. If so it would look much better and easier to make. It may need some modification to the fitting if the trays must be horizontal. As I read the drawing there are no shoes for the spare wheel and the control of the wheel is taken entirely by the cross tube. If this is so I fear torsional flexibility of the cross tube will allow too much vibration of the wheel. I suggest considering making the large tank sheet of thin tinned steel with holes only to pass filter and gauge pump through. Then over this part rivet and solder a pressing made from thicker tinned sheet suitable for carrying all the fittings and the spare wheel carrier, which latter would still be an aluminium casting. If a success it could give very high vent, good appearance economy, and rigidity. It seems worth a struggle. If sometimes rear wheel carrier is not fitted we could arrange to make the appearance good by suitable vent casting, which in any case might be an aluminium casting. Some of the clearances look small - i.e. end of filter in sump. There should be room for dirt and water. Other parts look rather too near one another. R.{Sir Henry Royce} | ||