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At the 1924 Model Engineering Exhibition the EXE 2.5" lathe was shown fitted to the company's "patented, self-contained friction motor drive".
There were two types of drive arrangement: the first consisted of a pivoting plate to which was fitted a large-frame, 0.25 hp motor together with a bracket bolted to its end that held a ball-bearing spindle. The spindle carried a fibre gear at one end that was driven, at a reduction ratio of 1 : 3, by a steel gear on the motor; at the other end of the spindle was a "friction disc" made from compressed sections of leather and arranged so that when the frame was pivoted by a foot-operated pedal it came into contact with the inside rim of the (normally foot-operated) flywheel and drove it by friction; when the foot pedal was released, a brake automatically stopped the lathe.
The second form of friction drive did away with the platform (carrying the motor and gearing) and instead a bracket carrying a countershaft was mounted on the rod normally used as a fulcrum for the treadle drive. The same type of ball-bearing spindle was used with a friction disc at one end, but in this case a pulley, rather than a gear, at the other.
The patent number for the drive was GB 165/24.
An additional fitting is shown in the illustration, an overhead drive unit that not only provided power to a milling or grinding head held in the toolpost but also to a drill press carried on a vertical bar socketed into lugs on the back of the stand.
Also at the 1924 Exhibition, and built by the EXE and displayed on its stand, was a beautifully detailed 1/4 scale working model of the 2.5-inch lathe. Even the leadscrew, so reduced in size that it required a 48 t.p.i thread, was true to the original, as was the spindle thread. Very unusually (and probably uniquely) the exhibit was a model of a lathe-maker's lathe built in-house on a prototype of the machine it represented.
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