GOUGE

In horology, the word gouge covers two distinct technical meanings. It first refers to a recess or circular groove hollowed into a component — Ratchet wheel, Crown wheel or Bridge — intended to locally retain the Oil or Grease near a point of friction, or to serve a purely decorative purpose; in all cases it is a hollow, not a protrusion, the concave shape promoting the retention of the lubricant by capillarity. The term then refers to a Cutting tool of the Engraver and the turner: a gouge is a Graver or a chisel whose cutting edge has a hollow profile, in a half-circle or V shape, which allows material to be removed by hollowing out and to create fillets and rounded patterns, notably in Guilloché (engine-turning) and in Engraving. The engraver has an assortment of gouges of various widths and curves, adapted to each type of line. In both uses, the notion therefore refers to a concave shape: a lubricant reservoir on one side, a hollowing tool on the other.