email: tony@lathes.co.uk
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Town Woodhouse (Woodhouse Mitchell)
396 Turret Milling Machine

An operation, maintenance and parts manual is available for this miller

and for other Woodhouse , Town and Mitchell branded machine tools

Manufactured during the 1950s and 1960s the "396" was named after its table size - 36" x 9" - and based on principles first incorporated in the pre-WW2 Bridgeport. However, unlike many similar machines, the Town Woodhouse did not clone or even copy parts of the American machine - but was an entirely original production. Built in Mk. 1 and Mk. 2 forms both versions of the 396 were of very similar appearance - but with the later model having nearly every casting changed and its vertical head being significantly altered and improved. The layout of the miller was entirely conventional with a heavy main column, in cast iron, formed as a stiff box casting with internal bracing and incorporating a small tool cupboard in its left-hand face - and the hollow base used as a convenient coolant tank. The knee rode on ordinary V ways, fitted with adjustable tapered gib strips, and both the elevating screw, and the table feed screws, were in the form of acme threads running through substantial bronze nuts with backlash elimination. The screws ran through particularly large end supports -  containing Timken taper roller bearings - and the zeroing micrometer dials were, at 3.5 inches, of a reasonable size for the time. The table was formed with a coolant tray around its outer edge - but with the 3 T-slots running through the end sections to maximize the clamping area - and had a T-slot machined down its front face to provide a location for the adjustable knock-off stops. Travel on the standard hand-feed table was 23 inches longitudinally, 9 in traverse and 17 inches vertically - however, with the optional power-feed attachment in place (giving 12 rates, in geometrical progression, from 0.5 to 9 inches per minute) longitudinal travel was reduced to 19.75 inches, but with handwheels still fitted at both ends. 
Spigoted into the main column the turret housing was 15 inches in diameter, graduated for rotation through 360
° and clamped in place by 4 bolts. The cast-iron ram was round - like a pre-September 1952 Bridgeport - and could be rotated in the same way, by a handwheel operating through worm-and-wheel gearing, and slid in and out by hand. The ram was locked into the turret by two pad bolts and the end opposite the vertical head machined to accept a slotting attachment.
The original vertical head had hand-powered downfeed and an interesting, though noisy, epicyclic gear arrangement that provided, in conjunction with the belt drive, 10 speeds from 100 to 2000 r.p.m. or, alternatively, 200 to 4000. At 3.75" the quill travel was a little shorter than the Mk. 2 and the high/low range selector used a lever instead of a dial. Much-improved, the robust Mk. 2 head had 9 speeds, from 80 to 2420 r.p.m., and was driven by a 1-h.p. motor through V-belts and a lathe-like "backgear" assembly employing some nylon gears to ensure quiet running. Marked
HIGH - LOW the backgear selector dial was conveniently positioned on the head's front face. Able to be rotated through 360° in the vertical plane about the turret overarm, both heads could also be tilted over - the mechanism for the latter being contained within a large-diameter cylindrical housing, with a degree ring engraved around its outer edge. The spindle could be raised and lowered through 4 inches of travel by either a hand lever - working through a flame-hardened pinion meshing with a rack cut into the quill - or by a fine-feed handwheel through worm-and-wheel gearing. A micrometer dial was fitted to the handwheel and a micrometer depth stop provided to aid accurate depth control. The most important improvement on the Mk. 2 head was the inclusion of power down-feed: two rates were available, working through a safety-overload clutch whose release setting was built in during assembly. Selected by a push-pull knob - and engaged by a similar control positioned beneath the fine-feed handwheel - the feed could be disengaged by hand, or automatically knocked off against the micrometer depth stop. The spindle and quill were in flame-hardened alloy steel, hardened, ground and with the quill housing honed for a perfect fit. The end of the 30 INT taper spindle was supported in adjustable needle roller bearings - the aim being to give the smallest possible radial clearance between it and the quill. A roller bearing took spindle end thrust whilst an upper taper- roller bearing ensured rigidity and accurate alignment. As a further contribution to smooth running the aluminum belt pulleys were balanced. On both heads the maximum clearance between spindle nose and table was 14.5 inches.
Well made and robust - the net weight was 1792 lbs (814 kg) - and once very popular, today a lack of spare parts limits the appeal of the 936 - though custom-made spares would still be a good investment to keep an otherwise-sound example running..

Mk. 1 Town Woodhouse Model 396 turret miller

Town Woodhouse Mk. 2 Model 396 turret miller

The versatility of a ram turret miller is clearly illustrated in this picture of the Mk. 1 head extended fully forwards whilst both swivelled and tilted through 90-degrees. The head was fitted with a No. 3 Morse taper nose, a roller bearing at the lower end and a rather noisy epicyclic backgear that gave, in conjunction with the belt drive, 10 speeds from 100 to 2000 r.p.m. or, alternatively, 200 to 4000. At 3.75". The quill travel was 3.75 inches.

Mk. 1 head with its spindle set in the horizontal plane

With a heavier built, the Mk. 2 head incorporated power down feed and,  driven by a 1-h.p. motor through V-belts and a lathe-like "backgear" assembly, 9 speeds from 80 to 2420 r.p.m. A number of gears in nylon were used in the gear train to ensure quieter running.

Clearly illustrated in this picture is the versatility of a ram turret milling machine - the Mk. 2 head being extended fully forwards while both swivelled and tilted through 90-degrees

Another view of the  Mk. 2 head with its spindle set in the horizontal plane

On both Mk. 1 and Mk. 2 versions the optional table power-feed attachment gave 12 rates of feed, in geometrical progression, from 0.5 to 9 inches per minute. With the unit fitted longitudinal table travel dropped from 23 inches to 19.75 inches - but with handwheels still retained at both ends. 

Driven by a 0.5 h.p. 3-phase motor the self-contained slotting attachment was carried on the back of the ram and retained against a 7-inch diameter, 4-bolt flange. It had 4 rates of stroke: 40, 60, 90 and 140 per minute. Both the main housing and the ram were manufactured in high quality cast iron - with the important gib strip in bronze and the maximum tool size 0.5 inches in square or round.  Pick-off gears, arranged in pairs, and accessible under a side cover retained by round knurl-edged nuts, were used to changed speeds whilst the stroke length was infinitely adjustable from 0 to a maximum of 2 inches..


An operation, maintenance and parts manual is available for this miller

and for other Woodhouse , Town and Mitchell branded machine tools

email: tony@lathes.co.uk
Home   Machine Tool Archive   Machine-tools Sale & Wanted
Machine Tool Manuals   Catalogues   Belts   Books  Accessories

Town Woodhouse (Woodhouse Mitchell)
396 Turret Milling Machine