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).
Investigations and future fitting procedures for Little End Bushes (Vandervell type).
| Identifier | ExFiles\Box 115\2\ scan0476 | |
| Date | 9th June 1939 | |
| 1020 To HPS.{Horace Percy Smith - Experimental Factory Mgr} c. to HPS{Horace Percy Smith - Experimental Factory Mgr}/RH.{R. Hollingworth} Rm{William Robotham - Chief Engineer}/Swdl.{Len H. Swindell}11/JH.9.6.39. Little End Bushes (Vandervell type), Regarding the slack which developed between the gudgeon pins and the above type of bushes on B.60 No.2. unit 29.G.VI. this has been taken up with the makers. Following a discussion with HPS{Horace Percy Smith - Experimental Factory Mgr}/RH.{R. Hollingworth} we give herewith a summary of Vandervells investigations for record and the future fitting of this type of bush. (1) Little end of connecting rod is bored to (.875 + 1/4 dia) as stipulated for these bushes (B.2203) incidentally the bore of the rod submitted was absolutely to size. (2) A small radius to be made on one side of the rod bore to prevent any sharp edge digging into the bush, and tear of the surface when the bush is pressed in position. (3) During the pressing in of the bush, this should be continuous and without a stop. (4) Vandervells leave several thous. in the bore of the bush for finally finishing to the requisite size. They recommend that this is carried out by a Burnishing bar the drawing of which we submit (SK.64) which serves two purposes. (a) That the bush is absolutely keyed back into the rod housing. (b) Gives excellent surface to finished size. In the same way as the pressing in of the bush, the burnishing tool should be carried through the bush without a stop. They have shown a series of dimensions on the burnishing tool ending finally with a size of .7525 which when passed through the bush leaves a bore of .7505 + 1/2. This contraction is dependant upon the structure of the connecting rod around the little end, therefore the dimensions of the burnishing tool, may require slight | ||