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).
The material for Goshawk II rear brake drums, specifically addressing the issue of low carbon content in mild steel.
| Identifier | ExFiles\Box 26\4\ Scan132 | |
| Date | 16th September 1921 | |
| Wd.{Mr Wood/Mr Whitehead} from BY.{R.W. Bailey - Chief Engineer} c. Hs.{Lord Ernest Hives - Chair} X.3409 X719 B Y6/P16.9.21. X.4357 - GOSHAWK 11. REAR HUB AND BRAKE X.3409 RE MATERIAL FOR BRAKE DRUMS The mild steel brake drums which we have received are too soft, the carbon being too low. This is not the O.O. fault, as I particularly wanted to try low carbon drums as an experiment to overcome glazing, but the carbon is so low in this case that the drum tears up and it cannot be hardened. We tried Ferosbestos which I have instructed my department to order three sets of, and the use of aluminium rivets with same to see whether this will overcome the cutting in on the present drum, but the point I have in writing at the moment is, I would like to know whether you can obtain pressed steel drums with a carbon contact of .26 to .33 approx. as a material of this amount of carbon will harden and enable me to try various brinell figures in connection with same. This would be, generally speaking, of the quality Thomsons propose for their frame pressings. BY.{R.W. Bailey - Chief Engineer} | ||