Rolls-Royce Archives
         « Prev  Box Series  Next »        

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).
Use of Packard type balance weights on Wraith III and Bentley 111 crankshafts.

Identifier  ExFiles\Box 132\1\  scan0028
Date  18th January 1938
  
BY/NS.{Norman Scott}
C. RM.{William Robotham - Chief Engineer}
C. HPS.{Horace Percy Smith - Experimental Factory Mgr}

WRAITH 111 & BENTLEY 111. CRANKSHAFT WITH PACKARD TYPE BALANCE WEIGHTS.

Please receive herewith E.CD.412 Packard type Balance Weights for Wraith 111 and Bentley 111 crankshafts.

It will be seen that the forging for the existing Wraith 111 crankshaft has not a sufficient allowance of metal to be suitable for use with the Packard type of balance weights, we think it worth while, however, to machine a crankshaft from an existing forging for experimental use, and if the deficiency of metal at the outer edges of the facings for the balance weights is no worse than shown on the design, it should be sufficient for the experiment.

We have followed the information given for the Bentley 11 crankshaft to LeC.5139 for determining the amount and angular position of balance, this may need correction to suit the crankshaft with larger journals and should be checked by experiment.

If at a later date, it is decided to use the Packard type of balance for Wraith 111 and Bentley 111 engines it will be necessary to make new dies for the forgings, in any case it is proposed to use the Packard type for Bentley 50, and this will demand new dies which should be made so that the forging would be suitable for all three engines.

Will you please detail and instruct experimentally.

DA.{Bernard Day - Chassis Design}
  
  


Copyright Sustain 2025, All Rights Reserved.    whatever is rightly done, however humble, is noble
An unhandled error has occurred. Reload 🗙