James Mills:1935 Review
Note: This is a sub-section of James Mills
Visit of the Iron and Steel Institute to the Iron, Steel and Engineering Industries of Manchester and District
James Mills Ltd., Bradbury, near Stockport.
At the time of the visit from the Iron and Steel Institute the rolling mill equipment of this firm will consist of 18", 12" and three 10" mills of which the first should be equal to anything in Europe for the production of really accurately rolled sections most of which will subsequently be cold drawn or precision ground.
In addition there is the largest cold drawing plant in the country capable of dealing with bars and rods from 8' down to 1/16" in diameter, drawn or ground accurately to size. The cold drawing plant produces standard sections, rounds, squares, hexagons, flats, etc. in all over a thousand different sections being produced.
Most of these are designed to eliminate machining operations in the production of finished parts. The machines for the precision grinding of shafts up to 30 ft. length and to limits down to 0.00025" are the most up-to-date available. Until this plant was installed it was considered good practice to produce round bars of diameter and upwards by turning. It will be appreciated that when ground the shafts are accurate along their whole length, whereas the majority of turned bars will vary from point to point. Bars can be supplied in any quality, ground finished, and stocks to B.E.S.A. specifications 32, 1935, grades 1, 2 and 4 are carried.
For engineering work of all kinds a large number of shapes are used the bulk of which were, prior to the Company producing bright drawn sections, machined from the solid. To-day it is equipped to produce almost any shape, having control of the production from the billet right through to the final drawing. The sections produced are ready to be cut off and fitted, thus eliminating the work of machining or grinding.
Mills super free-cutting steel, the outcome of collaboration between the firm's research department and the steel makers, is claimed to be the finest material available for cutting and screwing. With high quality, high-speed tools the following speeds can be attained together with long tool life and good finish:— Forming, turning, etc., over 400 feet per minute, screwing, 80 to 100 feet per minute, tapping, 50 to 75 feet per minute.
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