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).
New, improved endless leather vee-type fan drive belts from supplier Messrs. Ormerod for the 20HP model.
| Identifier | ExFiles\Box 75\3\ scan0206 | |
| Date | 28th September 1923 | |
| T M W HS.{Lord Ernest Hives - Chair} c. Mr Shelton. X4257 BY18-P28.9.23. 20HP. FAN DRIVE BELT. We have received from messrs. Ormerod, two more endless leather vee type belts which they have prepared as a result of their previous experience on the belts that failed. The two belts I left on your desk are not merely further copies of the original type, but the leather from which they are made has been tanned in an entirely different manner. The previous ones were all chrome tanned, these have been partly chrome tanned and then finished with oak bark tanning - the result is they have got the elasticity of the chrome without the excessive sponginess of the original belts. A further improvement they have incorporated is, that the original belts were made with a special cement and used in conjunction with seccotine - an examination of the belts that failed shew that the seccotine had hardened under the heat effects and was not satisfactory from that point of view. The belts in question can be run quite slack - there is no need to tension them up. Messrs. Ormerod assert that they will run equally well slack as tight, and in thinking the matter over it appears to me that if they will run slack there is a greater chance of the belt giving good service in a slightly slack condition than in a tight one, in as much as the rate of turn per unit of the belt is considerably less in the slack belt than it would be in the tight belt. Messrs. Ormerod pointed out to us that they have these belts on a number of cars which have done anything between 6000 and 10,000 miles. So far they have not had a single failure. Whilst they think the drive on our 20HP Fan is more arduous than the cars they are running on at the moment, they are of the opinion that the new belt should cover our requirements. AWB/C8 BY.{R.W. Bailey - Chief Engineer} By | ||