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).
Comparing the pros and cons of semi-floating axles versus fully floating axles.
| Identifier | ExFiles\Box 114\1\ scan0157 | |
| Date | 29th September 1938 | |
| 1015. To By.{R.W. Bailey - Chief Engineer} from Rm{William Robotham - Chief Engineer}/Gry.{Shadwell Grylls} c. Hs.{Lord Ernest Hives - Chair} c. Da.{Bernard Day - Chassis Design} c. Hdy.{William Hardy} c. Ev.{Ivan Evernden - coachwork} Rm{William Robotham - Chief Engineer}/Gry.{Shadwell Grylls}7/MH.{M. Huckerby}29.9.38. SEMI FLOATING AXLE. Hs.{Lord Ernest Hives - Chair} has asked for a memo stating the pros and cons of this axle compared with the fully floating variety. Several features included in the new design could, of course, be applied to a fully floating axle. These are:- (1) Preloaded diff bearings - cheaper to buy and assemble. (2) Hubs to suit bolt on wheels - cheaper. (3) Cheaper shape of axle tube. Setting these aside, the semi floating axle has the following advantages:- (1) Freedom from wheel driver knocks. (2) Cheaper (exact information to follow after material investigation by Les.{Ivan A. Leslie}) (3) Stiffer half shafts tend to decrease clutch jagger trouble. and the following disadvantages:- (1) Failure of a half shaft outside the wheel bearing would let a rear wheel come off. (2) A less severe accident than will damage a fully floating axle may bend the half shaft of a semi-floater. | ||