|
Manufactured by the Richyoung Industrial Co., Ltd. of 5F-1, No. 273 Ming Chuan Road, Taichung in Taiwan, this small bench-mount surface grinder had a somewhat greater capacity than others in its class. Fitted with a T-slotted, 6-inch by 12-inch table - with a longitudinal travel of 13.25 inches and in traverse of 7.125 inches - the Richyoung had a maximum table to wheel clearance of 8.875". Down feed of the head was controlled by a handwheel at the top of the vertical slideway, a pair of bevel gears turning the drive through a right-angle. Satin-chrome plated, the micrometer dial (like that on the table's transverse feed screw), was satin-chrome plated, crisply engraved and of a usefully large diameter. Rather oddly a ruler was provided to measure the setting of the grinding head - though why, when a grinder is expected only to remove a few thousandths of an inch of material, is a mystery… Longitudinal feed was by a very large, full-circle handwheel fitted with a decent handgrip - many similar grinders having ones that were far too small for comfort. Power came from 3/4 h.p., 110/220 Volt, 7.4/3.7 Amp single-phase motor - this turning at 3425 r.p.m. when fed with a 60 Hz supply and controlled by a simple (cheap-looking) on/off push-button starter. Instead of the expected belt drive to the spindle the drive was direct, the motor being flange mounted against the back of the spindle housing. Presumably the motor spindle would have been extended in some way to form that carrying the wheel - though it might, just possibly, have been through some form of flexible coupling. Was the motor fitted with a balanced rotor to eliminate the usual 1-phase motor vibrations being passed to the workpiece? Doubtful…. The grinder stood 31 inches high, was 36.5 inches wide and measured 33 inches front to back. Supplied with each new machine was a 7-inch diameter 0.5-inch wide grinding wheel, a tool box with the necessary wrenches, what was described as a "one-shot" lubrication system and a regulation wheel guard. Few surface grinders of similar size and capacity have been offered, with the best known of the miniature type including the American Sanford and the Builders Iron Foundry (the latter a simple, fairly crude type with an oddly arranged hand-lever table feed). In Pre-WW2 years the English Herbert Company offered a somewhat larger "Ball-bearing Bench Surface & Die Grinder" (and later a floor-mounted hand-operated model) and EXE their very fine bench machine. A French Company, Lipemec, produced the beautiful LIP 515, this having the same capacity as the Sanford SG-48 at 8" x 4" (200 x 100 mm), a somewhat similar base, saddle and table - but with an entirely different, double-column upright to carry the grinding head - the solid steel bars being hardened, ground and protected by bellows. Grenby, an American machine maker better known for their cylindrical grinders, made a slightly larger table-top unit with the design (in a modified form) used as the basis for the Australian Macson. In recent years a version of the "Grenby-Macson" has been produced in China to be sold under various brand names including Harbor Freight and Tormach. The Tormach, manufactured to a higher level of accuracy and finish is, today, available with automatic feeds and has travels of 6 by 12 inches - travels for the hand-feed Grenby are not known. Another example is the high quality, superbly constructed unit from the Swiss Bulova watchmaking company - though this model, like the Richyoung, might be considered too large and heavy for the description "miniature" to be applied. Other, larger, hand-operated surface grinders commonly found include the 2B and 2LB Brown & Sharpe models, the Capco, Eagle, Superior, Feinprüf, Jones & Shipman Model 540H and Norton Model TS.
|
|