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Manufactured during the 1950s, the Richmond turret milling machine was designed along the lines of the highly successful Bridgeport Series 1 and used a vertical head already in production as an accessory to mount on the Company's and other makers horizontal machines, the "Hyspeedmil".
Initially sold for £340 during 1956 as the rather basic "Type 1" with all-hand feed to the table and knee movements, within 12 months two further models were on sale, the improved "Type 2" and "Type 3" with automatic table feeds that cost an additional £162. Driven by a separate 1000 r.p.m. 1/2 h.p. motor through gears, the compact feed box was slung beneath the right-hand end of the table. A range of six speeds was provided spanning 1/2" to 12" per minute controlled by a direct-reading dial and lever - the latter being moved left or right to give the corresponding table movement. On the "Type 3" model two further refinements were a mechanism to enable the feed to be automatically reversed and a "pick feed" to drive the cross travel - this arrangement giving the operator the facility to set up a fully automatic feed cycle. Fitted to all models, the 38" x 9" table had three 9/16" T-slots on a spacing of 2.25" and travels of 24" longitudinally by hand, 20" under power, 9" across by both hand and power and 14" vertically. As on many machines of the ear, the table had a facility to hold, along its front surface, high-precision cylindrical end measuring rods, micrometer barrels and dial indicators that read to one ten-thousandth of an inch.
All sliding surfaces associated with the table movement were equipped with tapered grip strips and large, 3.5-inch diameter satin-chrome finished micrometer dials - their generous size intended to help with jobs such as die and mould production and jobs of a toolroom standard.
Initially made in aluminium, the main body of the Hyspeedmil was later changed to cast iron and other improvements incorporated including a sleeve housing extended to give a quill with an extra 1/2" of travel greater support when fully extended and the spindle pulley changed from aluminium to cast-iron. A precision assembly that used high-grade Timken taper-roller bearings, the No. 3 Morse taper spindle and its supporting quill were hardened and ground and the quill bore honed. Clamped into a turret that could be rotated 360° horizontally, the round, solid steel overarm and head assembly could be swivelled through 360° in a vertical plane with a setting accuracy to within 5 minutes of arc by use of a vernier clynometer. Power came from a vertical, flange-mounted 3/4 h.p. 3-phase motor with drive to the spindle by an A-section V-belt that passed round balanced pulleys running in their own precision ball races to relieve the spindle of belt pull. As an optional extra a backgear assembly could be incorporated that worked on the two lowest speeds. On the direct-drive model (listed as the Type A) six speeds were provided of 400, 645, 1000, 1600, 2700 and 4100 r.p.m. with the backgeared version (Type B) having eight of 130, 215, 400, 645, 1000, 1600, 2700 and 4100 r.p.m. Quill travel was 4", controlled by a 4-lever capstan handwheel through fine-feed worm-and-wheel gearing and a rack, one complete turn of the handle moving the quill 0.250" - this working in conjunction with the usual sort of screw depth stop whose indexing collar graduated to read to within 0.001; unfortunately the assembly lacked a quick-action drilling handle.
A number of accessories were offered including a complete bolt-on "Hydrotracer" assembly for copying work that could be fitted to either the Type 2 or Type 3 machines with their automatic power table feeds. The system, listed at a very expensive £730, followed established design principles with a sensitive hydraulic tracer unit connected to and operated by a self-contained motor-driven hydraulic accumulator and tank unit mounted at the side of the machine. Stylus pressure could be adjusted from 8 ozs to a few pounds and fluid pressure from 50 to 500 p.s.i. In addition a complete "Duplex" model was available that mounted two heads side-by-side.
As on the Bridgeport and other makes of turret miller, a slotting head was available to fit at the other end of the ram and able to be swung round into position. The unit was in cast iron and self-contained being driven by a 3/4 h.p. motor through 3-step aluminium V-pulleys to worm-and-wheel gearing. The stroke rate was fixed at 2-inches (and not adjustable) with rates of 45, 75 and 120 per minute.
Should any reader have a Richmond Turret miller, the writer would be interested to hear from you.
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