The compass saw is used to cut curved lines and especially to cut a hole in the center of a shelf. It resembles the handsaw but is shorter (approx. 20-30 cm) and has a much narrower blade (approx. 1.5-2 cm) that tapers to a point and is fixed in an open pistol grip or a straight handle. There are now small compass saws with straight metal handle in which the blade slides, so that the artisan can have the latter protrude just as much as necessary.
The joiner drills a hole in the shelf and inserts the end of the saw into it. Despite the lack of rigidity, this saw usually works when pushing. [MOT]