Back Rest
American Watchmaker and Jeweler (1892)
Among the many tools that watchmakers can make for themselves, one of the most useful is the tool illustrated in Fig. 273. It is a modification of what machinists call a "back rest." The only points in which it differs from that employed by the machinist is the shape of the jaws and the mode of fastening to the lathe bed. a shows the rest in position on the lathe bed, looking from right hand end of bed; B shows the base, looking from above, in direction of arrow k; C shows bolt for binding it to the lathe bed. It does not seem as though it needed much explanation, as it will readily be seen that the head d of bolt, passes up through the longitudinal slot in lathe bed, through the round hole in base of back rest, and slipped back into slot m, when about half a turn of the nut g binds it firmly to the bed. The washer h, on the end of binding screw, is riveted or soldered in place, and should be close enough to nut g to allow only about half a turn to loosen the bolt, as that is sufficient, and more would be time lost in running the nut back and forth to bind or loosen the rest. It will be seen that when the nut g is slackened it binds against the washer h, and it will stay there, and be just where you want it when you want to use it again. The jaws are of hard brass; about three sets, with points of different widths, will cover a good range of work. Those shown in Fig. 273 are suitable for such work as pivoting small French clock pinions, etc. It will be observed that the jaws are so made that they may be changed by slightly loosening the screws. The screw heads should have thin steel washers under them.
What Has Changed in the Last Century
The tool itself has barely moved: a steady rest that supports a slender pivot against the cutting tool works in 2024 exactly as the American Watchmaker and Jeweler described it in 1892, and the 8mm and 10mm watchmakers' lathes of the WW pattern are still in production with back rests among their standard accessories. What has changed is the assumption behind the article, that a watchmaker would file up his own jaws from hard brass and fit his own clamping bolt; steady rests, jewelled centres and tip-over rests are now catalogue items, and the pivoting work described here is far rarer since balance staffs, stems and pinions are ordinarily bought ready-made and simply swapped in. The quartz movements that arrived in the 1970s removed most of the repair trade that made such benchwork routine, though hand-turned pivots survive in high-end restoration and in the workshops of independent watchmakers, where old lathes of exactly this vintage are still prized and used.
Written for this edition, 2026.