Wiktionary
slotting machine
n. A reciprocating machine tool used to cut mortises and to shape openings
Usage examples of "slotting machine".
This was the ease with the self-acting mule, the wool-combing machine, the planing machine, the slotting machine, Nasmyth's steam arm, and many others.
The toolbit, as tall as a man, of one slotting machine seemed to require regular replacement from a magazine after it worked on one of the hexagons, but the other tools did not noticeably lose their edges.