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).
With a data table for tooth depth and chordal thickness, recommending a new process for forming oil grooves on splines.
| Identifier | ExFiles\Box 128\3\ scan0071 | |
| Date | 8th March 1940 | |
| -2- Rm{William Robotham - Chief Engineer}/FJH.{Fred J. Hardy - Chief Dev. Engineer}3/MH.{M. Huckerby}8.3.40. Depth below top of tooth. Chordal thickness. 0 0.050 0.125 0.175 0.250 0.025 0.106 0.190 0.2255 0.247 Concerning splines, we do not at present have a separate grinding operation for removing the sharp corners from the top of the splines. We therefore recommend that the oil grooves under the 3rd. speed gear of the junior box should be formed by lifting the hob that is used for roughing the splines and cutting shallow grooves up to the shoulder. We are investigating the possibility of cutting grooves in existing S.M. steel cones for the purpose of trying the principle of cones running on the top of gear teeth. Rm{William Robotham - Chief Engineer}/FJH.{Fred J. Hardy - Chief Dev. Engineer} | ||