Mortising Machines

The mortising machine for wood work consists essentially of an ordinary auger, which bores the holes, and a chisel for cutting the corners so as to produce the square or rectangular mortise that is usually employed in wood work.

The chisel is reciprocated and its driving spindle is provided with means whereby the chisel may be reversed so as to cut on either the sides or the ends of the mortise. The chisel is fed gradually to its cut.

Fig. 3225 represents a mortising machine for the hubs of wheels.

The auger spindle is here fed vertically by a hand lever, the depth bored being regulated by a rod against which the hand lever comes when the hole is bored to the required depth.

Fig. 3226 represents a mortising machine in which the mortising tool consists of a hollow square chisel containing an auger, and having at its sides openings through which the cuttings escape.

The chisel is rectangular in cross section, but its cutting edges are highest at the corners, as may be clearly seen in the figure.

The work is firmly clamped to the work table and simultaneously to the fence, the upper hand wheel being operated to bring the work-holding clamp down to the work, and the lower one to clamp it so as to press it to both the table and the fence at the same time.

The chisel bar is mounted horizontally in a slide way on a substantial bed that is mounted on a vertical slideway, which enables the chisel bar to be set for height from the work table. It has a horizontal traverse motion or feed, the amount of this motion being governed by the horizontal rod with its nuts and check nuts as shown.

The auger runs continuously, and works slightly in advance of the cutting edge of the chisel, which is passive except when making the mortise.

The chisel bar and auger have a slow, reciprocating motion, and will complete a hole the size of the chisel used. An inch chisel will cut an inch-square hole, consequently a mortise 1′′ × 4′′ would only require four strokes forward to complete it. It has a capacity to work mortises from ⁄4′′ to 3′′ square, and 5′′ in depth, and any length desired. The boring spindle is driven by an idler pulley, direct from the countershaft.

The bed upon which the timber is placed to be mortised is gibbed to a sliding frame, which allows it to be set to any position, with the chisel straight or at an angle. It is adjustable to and from the chisel bar, to suit the size of material, the under side of which always remains at one height. Adjustments are provided for moving the carriage forward, for regulating the depth of the mortise, the position of the chisel from the face of the material, and the adjustment of the chisel bar, controlling the mortises to be made in the timber.

Two treadles are used upon the side of the machine; the pressure upon one carrying the chisel bar attachment forward, completing the mortise, while the other will instantly force it back when it is desired to withdraw it from the wood, without allowing it to cut its full depth. Provision is made by stops for regulating the length of the stroke as well as the depth of the mortise.