Broadhead-Garrett J-Line Shaper
USA
An Operator's Manual and Parts List is available for this machine
Broadhead-Garrett were based at 4560 East Street, Cleveland, Ohio (with a Western Division at 161 Commercial Circle, Sacramento, California) and manufactured this neatly designed 8-inch stroke shaper in the 1950s and 1960s. The company is still in existence (2005) bit no longer has anything to do with machine tools).
With its completely enclosed expanding and contracting variable-speed drive system the Boradhead-Garrett was of special appeal to educational establishments; no opening of doors or moving of belts was required to change speeds - and it was also possible to mount an immediate demonstration to the students of the effects of running the machine either too quickly, or too slowly. The motor-drive system was mounted within the cabinet base, with a single V belt taking the drive to a countershaft which ran in plain bearings, held within cylindrical brackets spigoted into holes on each side of the main body. The simplicity of this arrangement was completed by a chain, which carried the final drive from a small sprocket in the middle of the countershaft to a large-diameter sprocket bolted to the face of the crankpin-drive plate.
The table-box table had three T slots in its top and right-hand surfaces and was elevated (maximum travel 5.5 inches) by a screw and bevel-gear assembly; although it could not be swivelled, the table was very well supported at the front by a two-slot bracing arm and adjusted to the body by a tapered gib strip. The table could be driven through 11.5 inches of travel in both directions under power - a safely-enclosed pawl assembly on the end of the feed screw enabling the operator to set the drive quickly and easily by lifting and turning a pin through one quarter of a turn for each power or neutral setting. Each tooth on the pawl gave 0.002" of feed and the adjustment was such that, working at single tooth increments, feed rates of 0.002", 0.004", 0.006", 0.008", 0.010" and 0.012" per stroke of the ram were available.
A particularly useful 5-inch capacity swivelling-base vise, with jaws 1.5 inches deep, was fitted as standard whilst a rotary table and a set of indexing centres - both of which were specially made for the machine - were on the options' list.
The tool head could be rotated through 45 degrees either side of centre ,and was fitted with a zeroing micrometer dial..