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 modifications and cost analysis for the Wraith III front hub.
Identifier | ExFiles\Box 10\4\ 04-page11 | |
Date | 19th March 1937 | |
SECRET. 656 To HY.{Tom Haldenby - Plant Engineer} Copy to Ds. Rm.{William Robotham - Chief Engineer} RWC. HPS.{Horace Percy Smith - Experimental Factory Mgr} Rm{William Robotham - Chief Engineer}/Les.{Ivan A. Leslie} H/PSN. E/EV.{Ivan Evernden - coachwork}1/MN.19.3.37 North Wraith III Front Hub. -------------------- Design research work has been in progress for some time with a view to simplifying the construction of the Wraith front wheel hub. On W.Sch.5070 herewith we show the finalised design. The hub is modified only slightly by the elimination of the undercut on the wheel cone and the casting at the back to take the oil retaining nut. The main modification concerns the oil retaining device at the back of the hub and this now consists of an aluminium die casting held on by studs. The fine limit on the turned portion of the stub axle has been eliminated by a modification to the oil retaining device. The oil retainer DW.996 is shown of thin gauge metal as already detailed, but reduced in length to 1.438" in order that the contact spring GB.2439 may give the load specified on the detail drawing. We understand that as the detail GW.996 is dimensioned the load on the contact is less than that called for. The design of this hub should be put in hand for the first Wraith III. It will be noticed that we have omitted the bronze cone in the wheel nut, in fact we have never asked for it, but we understand that the Expl. Dept. have arranged that a certain number of wheels and nuts having this feature should be supplied and tested. We certainly do not wish to incur the added expense unless it is found to be necessary. Enquiries have been made concerning the oil retaining cap GW.996, for which Messrs.Dunlop quoted 1/8 each, and the Order Office have obtained a quotation of 3d. each unmachined plus some tool charges, from another source. With respect to the price charged for the hubs made in our factory, it has been shown that these cost 3/6 less | ||