gim-peg

plural gim-pegs

1. historicalAn adjustable flanged bent iron rod that rises from the workbench of a lapidary and which is used as a guide for the vertical angle when cutting facets, and also to support the arm of the lapidary.

   A very important substitute for the gim-peg socket, already described, is the dial, by means of which facets can be cut with great precision.

   1894, The Encyclopaedia Britannica

   2 more examples

   The squares are then polished in the same order, the gim peg being carefully adjusted for height between every row, in order that the stick may be inclined at exactly the same angle as that employed for cutting the squares.

   1850, Charles Holtzapffel, Turning and mechanical manipulation

   the lower end of the rod passes through a hole or mortise in the bench, and is fixed by a wing-nut beneath, in order to allow the gim-peg being twisted round to different positions, according to the distance it is required to be placed from the mill.

   1874, Oliver Byrne, Handbook for the Artisan, Mechanic, and Engineer