A planer works on the same principle as the shaper, the shaft to which the tight pulley is fastened being geared to the platen or table so that the table runs back and forth. The work is fastened to the platen or held in a chuck. The tool is held in a head which may be raised or lowered to suit the work. This head is fed across on a cross-guide by means of a screw actuated by a ratchet-feed. Heads are also placed on the housings so that they may be adjusted to plane on the edges or sides of the work. Considerable skill is required to fasten the work, so that when completed it will not spring out of shape, but will remain true.