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Often greatly underrated, even by experienced engineers, the shaper is a machine-tool that was displaced for many years by a flood of cheap, far-eastern vertical millers. However, being a surprisingly versatile tool the shaper is staging something of a renaissance - and the many knowledgeable enthusiasts who baulk at spending large sums of money on easily-damaged tooling for their miller know that much the same effect can be obtained with a shaper and a few pence worth of cutting tools. In addition, you don't need an expensive, difficult-to-operate tool & cutter grinder to sharpen tools - just an ordinary "double-ended" grinder. As a bonus, whilst the machine is working, there is something inherently entertaining and satisfying in its regular mechanical motion - and an almost Victorian atmosphere surrounding the way in which it does its job.
An important American contribution to the field of shapers intended for amateur use was the neat Atlas 7-inch. Introduced during 1938 it was also badged, like many other Atlas products, as the "Craftsman" for distribution in the USA by the mail-order company Sears. It was also sold as the "Acorn" in the UK and the Austolite when manufactured (or marketed) by Fred Price Engineering in Australia.
The machine table had just under 5" of height adjustment whilst the five-speed, automatic cross feed worked in both directions (at the flick of a pawl lever) and fed the table under the cutter at between 0.005" and 0.025" per stroke of the ram with a total sideways travel of 9.375". On early models the housing for the table ratchet feed was in cast-iron, with the first having a plunger to operate reverse and the later type a lever. Expensive to produce, this item was quickly replaced by one in ZAMAK, a choice of material that would prove to be a considerable test of its strength and reliability. The 6-inch wide and deep box-form table was provided with three T slots in the top surface, two slots in each of the ground-finish side faces and was supported by an adjustable 3/4" diameter rod which travelled with the table as it moved - so bracing the front of the work table and eliminating, to large extent, the flex caused by taking heavy cuts. Unfortunately, the first production machines were without any form of table support - a significant omission which strongly suggests that prototype testing might well have been less than thorough.
Neatly mounted on the rear of the machine, the self-contained V-belt motor-drive system carried a 1725 rpm single or three-phase 0.5 hp motor that provided four stroke rates of 45, 78, 122 and 186 per minute. The drive to the ram was though properly-engineered, well-supported gearing with the larger wheel 1" wide, of 10 d.p. and made from a semi-steel iron. The slotted crank arm was in nickel-chrome-vanadium with a ground finish on its outer surfaces and ground and lapped on the inner "slide" ways. The upper crank pin ran on an Oilite bush with the stroke-positioning screw, crank pin and slide lubricated through a wick oiler contained within the ram clamp screw handle. Lubrication for the slide must have been found inadequate for later models had an oil hole drilled through the centre of the "slide cover plate". The large "bull" gear was supported by a roller bearing on its near side to absorb the considerable radial loads placed on it and, at the end of its shaft to take thrust loadings, a deep-groove ball race. The drive spindle was hardened and ground, ran in roller bearings and carried pulleys which were dynamically balanced. The belt-tensioning lever doubled in duty as a clutch-come-brake and, acting on a brake shoe within an extra drum attached to the drive spindle, it meant that the machine could be stopped quickly - and without having to switch off the motor.
A rather good, heavily built swivelling -base 4" machine vice with steel jaws was fitted as standard: like all good shaper vices it was shallow (only 3" tall) but long enough (at 12") to hold a substantial lump of material. One crank handle was supplied with the shaper and, magically, it fitted all the controls: the vice, table elevation (with a supplied extension piece), hand cross feed, feed and stroke-length adjustments - and the stroke positioning.
Of particular interest to the amateur machinist was the fact that this machine, with its built in mounting tray, was one of the very few heavy-duty shapers capable of being bench mounted, requiring a space of just 18" x 32.5". Owners report that the shapers is capable of holding its accuracy over a long and strenuous life. In basic form with a vice, and in the year of its introduction, it weighed 240 lbs and was priced at $198 - though with a motor and guards the cost rose to around $260 and the weight to just over 310 lbs..
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