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).
Standardisation of parts for the Phantom III, specifically the Big End Bearing Bush made from AC.9 die-cast material.
| Identifier | ExFiles\Box 171\5\ img038 | |
| Date | 16th May 1938 | |
| RR 755 (10H) (49968) 19/10/37 C.E.Co. COMPLETED 22.9.38. PHANTOM III STANDARDISATION OF PARTS Date Issued: 16.5.38. Sheet No. P.27. Drg. No. E.89244. L.O.P.S. Description: BIG END BEARING BUSH (AC.9 DIE CAST) Purpose: Ease of casting with consequent reduction in scrap, also reduced mat. cost by die casting approximately to size. Brief Report and Remarks: The AC.9 material was evolved for ease of casting as compared with previous bearing alloys in AC. material. Bearings of this AC.9 material were run over 40 hrs. severe conditions both in die-cast and centri-cast form to reduce material cost, on a Bentley II unit. Of the two types the die-cast were the best and almost unmarked after the run whereas the centri-cast although very good revealed slight crack in one big-end and was characteristic of centri-cast alloys previously tried. When recommended for Introduction: Report References: By: Rm{William Robotham - Chief Engineer}: Da{Bernard Day - Chassis Design}: Mx{John H Maddocks - Chief Proving Officer}: Old Parts: Material £0.7.5., Labour £0.7.8., Burden £0.13.5., Total £1.8.6. New Parts: Material £0.7.5., Labour £0.6.11., Burden £0.12.1., Total £1.6.5. Decrease in Cost £ 0.2.1. ARH 16/6/38. Cost of Tools £ 10.0.0d. Production Position and Comments: Bearing Bushes produced as die castings in AC.9 differ only in respect of material specification from those previously included under Standardisation Sheet P.24, as die castings in AC.6. The above saving in cost results from the experience gained and is due to improved machining and casting methods since the Bushes were first produced in die cast AC.6 material. SEE OVER RHC{R. H. Coverley - Production Engineer}'S COMMENTS. Authorisation to Proceed. Introduce on the 171 Chassis in D Series. Signature Date 20/9/38 | ||