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).
Alterations to achieve a 3-degree caster angle for the B.V. car.
| Identifier | ExFiles\Box 153\1\ scan0208 | |
| Date | 20th March 1939 | |
| 1306 + 450 To Da.{Bernard Day - Chassis Design}.. from Da{Bernard Day - Chassis Design}/DB.{Donald Bastow - Suspensions} c. Rm.{William Robotham - Chief Engineer} Rm{William Robotham - Chief Engineer}/FJH.{Fred J. Hardy - Chief Dev. Engineer} c. Ev.{Ivan Evernden - coachwork} Da{Bernard Day - Chassis Design}/JD.{J. Draper - Frames} Da{Bernard Day - Chassis Design}/DB.{Donald Bastow - Suspensions}5/N.20.3.39. 3º Caster Angle, B.V. In order to obtain the 3º caster asked for in Rm{William Robotham - Chief Engineer}4/R.16.3.39, when the car is occupied by the driver only, the actual caster in relation to the level top of frame is 1º 2', using the latest normal loaded positions of the front and rear wheels, and the load differences between loaded and one up and the spring ratings of Rm{William Robotham - Chief Engineer}/FWK5/JH.1.3.39 for 8.B.V. car. The angles of the yoke piece boss for the king pin will then be altered from those of FB.4305/6. In FB.4305 for instance the 3º47' angle in the left hand view becomes 3º38', and in the next view to the right, instead of being vertical, the king pin boss centre line is inclined to the left going down at an angle of 0º23'. This angle is in the same direction to the vertical as the 1º20' angle of FB.3675. No alteration should be made to the 1.739 and 1.567 dimensions fixing the bottom end of the king pin boss, and the hole for the king pin will then be approx .020" out of centre at the top of the boss. This amount is small enough not to cause a foul there and means that the new yoke piece embodying the angles given above can be made from the existing forging. The alteration to caster also affects the cross steering lever, and instructions regarding this will be sent as soon as possible, either in the form of a memo or a scheme. Da{Bernard Day - Chassis Design}/DB.{Donald Bastow - Suspensions} | ||