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).
High scrap rates for Slipper Drive Friction Discs and a proposal to test a new material.
| Identifier | ExFiles\Box 26\4\ Scan265 | |
| Date | 21th October 1924 | |
| Y 4388 C327 Hs.{Lord Ernest Hives - Chair} -- BYS/H.{Arthur M. Hanbury - Head Complaints} 21. 10. 24. ------------------ SLIPPER DRIVE FRICTION DISCS. ----------------------------- At the moment we are using Continental Bakelite Friction Discs. We are having to scrap about 60% of the discs we produce, owing to the fact that the discs themselves vary in thickness. I can permit a disc to vary 1 1/2 thous. but I do not think it is permissible to go higher than this on a thickness variation as to do so would affect the characteristics of the slipper wheel. I would like to try some "Halo" instead of Continental Bakelite, to see whether it would not give equally good results, because from our experience, at least in rather thicker material, "Halo" can be bought almost dead parallel, and one would expect that to be the case in as much as the discs are, or can be, pressed to size and shape, whereas the Bakelite material once it has been formed and baked you can do nothing with it in regard to reducing its thickness by putting it in a hydraulic press. We have attempted to lap the Bakelite material, but the result is that the lapping cuts through to the fabric, tears this up and presents an entirely different face to the friction surface. I am raising this point because of the exceptional amount of scrap. It does not mean a great deal of cost per car, but it looks an enormous amount of scrap when you view it in the bulk. BY.{R.W. Bailey - Chief Engineer} By | ||