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).
Multiple component failures, including issues with the crankshaft, con-rod caps, and front cross member.
| Identifier | ExFiles\Box 82\3\ scan0326 | |
| Date | 26th May 1935 guessed | |
| ( 2 ) In our opinion, the breaking of the tabs was in-directly due to the excessive crankshaft period we had. The other is that the shells of the bearings are too weak to withstand the hammering blows. The thin steel shell is hardening up under the process, and taking a set up of a smaller diameter than the con-rod. We send you sketches of this. Another feature is the question of heat. The bottom con-rod caps of N° 3 & 4 are a deep blue;(see sketch) 2 & 5 are not quite so blue. I & 6 show no signs of heat and are still undis-coloured. The tabs show definate signs of hammering on the faces of the con-rod joint. The bronze metal is broken away from the steel at the ends of the tabs. The steel portion of the tabs stand proud of the lead bronze showing the hammering effect. The bronze bearings show the heat effect by the carbon deposit on the bearing itself. The shell shows itself to be fidgeting. We trust that the above is clear to you. With regard to Paris dépot. We have no hope of them fitting a new Crankshaft, and having to line the bearings up. Our Crankshaft, was the first Bentley they had seen, and I've not much confidence in them to scrape or let in bearings. We have now one more failure to report. The front cross member taking the support of the Radiator and wings has cracked, and pieces broken out where the bolts hold.it to the distance piece in the frame. One bolt had disappeared and two others were loose. We have tightened these bolts up previously, but did not report upon it, as we wanted to make sure that they were coming loose. However there is no delusion and the fouling of the Matrix shield, and the wing stay hitting the front axle control, is due to the above. We will take the cross member out and have it welded, if you so desire. ----- GWHancock G.W.H. | ||