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).
Heat treat specification from the Cadillac Motor Car Company, detailing physical properties, treatment processes, and general specifications for wire.
| Identifier | ExFiles\Box 17\6\ Scan217 | |
| Date | 16th July 1931 | |
| FORM 2903 3M 1.30 MCO. HEAT TREAT SPECIFICATION CADILLAC MOTOR CAR COMPANY No. 83 DATE 7-16-31 PHYSICAL PROPERTIES ROUGH Swedish Wood FINISHED Refer to detail drawing. Test 100% HEAT TREATMENT ROUGH FINISHED After Forming: Heat to 1500ºF.{Mr Friese} Quench in oil. Temper at 680ºF.{Mr Friese} for 30 minutes in Homo. Cool in air. Straighten and set. Re-temper at 680ºF.{Mr Friese} for 30 minutes in Homo. Cool in air. GENERAL SPECIFICATIONS Rockwell Hardness approx. C-47 to C-51. VH30 approx. 470-530. Must stand 9 hours continuous running, at period of greatest vibration or noise, without breakage or set of more than 2% of original weight at position of greatest load when assembled. Test 1/2 of 1%. NOTE: Each bundle of wire is to be cut in half, and specimens of wire approximately 9" in length are to be cut from each end of each half bundle. These specimens of wire are to be etched and examined by supplier and submitted to Cadillac for approval. All bundles to be held by supplier for Cadillac approval before coiling into springs. CHANGE RECORD DATE | MARK | ORDER NUMBER | DETAILS OF CHANGE 2-3-31 | - | C-56107 | Rockwell Hardness approx. C-47 to C-51. VH30 approx. 470-530 changed from Finished Physical Properties to General Specification. 2-3-31 | - | C-56107 | "Temper at 680ºF.{Mr Friese} for 1 hour in Homo Furnace" changed to "Temper at 680ºF.{Mr Friese} for 30 minutes in Homo. 2-3-31 | - | C-56107 | General Specification note changed. 7-16-31 | - | C-57774 | General Specification note changed. APPROVED JorS | ||