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Also marketed under the "Craftsman" brand name by Sears the Atlas Horizontal Miller was a very heavy but compact and useful machine that demonstrated the typical attention to detail and care in design that marked the products of the American Atlas Press company. The picture above shows the machine as introduced in 1941; in later years the tough but cosmetic and (unnecessary) cover above the overarm and spindle was dropped and provision made so that a bracing bar could then be added between the knee and arbor end. The miller was marketed in various forms and could be had with and without an integral motor and countershaft unit and with screw or lever feeds to the table - the option was also offered of an interesting "Change-O-Matic" table-drive unit.
An 18.5" x 20.5" cast-iron base was used and the machine stood 22" high, 32.5" wide and 25.5" deep. The 1" diameter No. 2 Morse taper spindle carried a 10-pitch NF thread, ran in Timken tapered roller bearings and was driven by a side-mounted, 0.3 hp motor mounted on a neat self-contained all-V-belt-drive countershaft unit. The inclusion of a 6.5 : 1 ratio "backgears" (3/8-inch wide 20 pitch) meant that a total of 16 speeds were available of: 62, 130, 212, 440, 450, 870, 1400 and 2870 rpm. - a very useful range, especially the slow speeds which, being gear-driven, could transmit lots of torque and enabled remarkably heavy cuts to be taken. The arbour could be supplied in either a 1" or 0.875" diameter. The drive belt was an unusual size of steel-band reinforced V belt - which has caused some replacement problems in recent years; one solution is to use a "Wedge belt", a deep-sided, heavy-duty version of the standard V belt. Unfortunately the 2-step motor pulley was also a non-standard Atlas item: the two diameters being 3.35 and 1.75 inches and a bore of 0.620"
A solid steel 11/2-inch diameter bar 14.5-inches long formed the overarm, supported at its outer end by cast-iron bracket fitted with an "Oilite" bronze bearing and with the whole covered by a cast-iron shield that had the effect of making the arrangement look far tougher than it was and hinting at a more modern, dovetail design. Made from a heavy grey-iron casting the 4.5" x 18" table was 13/8" thick and finish ground with three slots in its top the central one being a conventional T-type whilst at either side V-slots were provided for holding bar stock. Power feed was fitted, the direction of which could be quickly changed by a neat, lathe-like tumble reverse mechanism. The table power feed incorporated an ingenious 32-speed table drive known as the "Change-O-Matic", a device similar to the "Pick-O-Matic" carriage-feed assembly offered as an extra on 10-inch Atlas lathes for a short time just after WW2. The unit was covered by a large cast-iron housing that doubled as the carrier for the gear train and provided rates of feed between 0.186" and 11.25" per minute - a window on the face of the Pick-O-Matic cover showing the table feeds available whilst a large knurled knob protruding from the left-hand face selected the desired feed speed. All feed screws had Acme-form threads with that for the knee elevation being a telescope type that saved space and allowed the machine to be bench mounted without the need for the screw to drop down into the cabinet. The table travel was 9.1875" longitudinally, 3.375" in traverse and 6" vertically.
A range of bolt-on accessories was available including a two-bolt swivel-base machine vice and 51/2" diameter rotary table (that shared a common base casting similar to that used on the Atlas four-bolt shaper vice), automatic (pumped) and gravity-fed coolant systems, index centres with 9 index gears of: 36, 40, 44, 46, 48, 52, 54 and 64 teeth, an outboard arbor support, light unit, both wooden and metal cabinet stands - and the usual selection of bought-in side-and-face cutters and slitting saws.
The horizontal model was the only miller in the Atlas range and it is surprising that they failed to list a complimentary vertical machine; incredibly, they did not even list a conversion vertical or slotting heads, despite such items being commonly available for other makes. However, during the late 1940s and early 1950s at least two third-party suppliers, Marvin Machine Products of Detroit and an unknown makers, offered a neat (non-quill feed) vertical attachment, and (from Marvin only) a slotting unit.
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