MORTISING MACHINES. The Fag Cal. Matti:dna, Recessing, and Boring 3fachine, shown in Fig. 1, is for mortising by a rotating cutter, as in heavy timbers. Both the cutting and the boring tools work in a heavy spindle, which has an adjustable frame gibbed to a column for vertical movement. There is also a horizontal adjustment for governing the depth of the recesses, which are gauged by a suitable stop on the front of the frame. The weight of the frame is counterbalanced. The table bearing the timber to be mortised runs on large rollers, and has either hand or power feed, as desired ; the power feed being used to feed from one mortise to the other, and the hand feed to work from one end of the mortise to the other. The table is made in sections. and may be of any length desired ; the roller stands, being independent, may be set at any distance apart wished. The machine may have an auxiliary boring machine at one side towards one end. This machine works with a cutter which first bores its way into the side of the piece being mortised, and then, by cut ting on its side, extends the hole to any desired length ; making mortises having semi circular ends. They will, of course, work to any desired depth, making either a blind or a through mortise, as desired.
17te Egan, Antomatie Square-chisel Cur Afortiser and Tenoner, Fig. 3, will not only cut heavy mortises, but make end ten ons, gain, or mortise clear through a timber 9 in. thick, and countersink for bolt heads. 'the frame consists of a casting cored out at the center, and bearing at one end a knee in which the square chisel bar plays, and on its top, at end from the knee just mentioned, a table having an up right bracket, against which the side of the timber to be mortised bears. A clamp piece on this bracket holds the timber down. There is a dead roll in the table, for facilitating feeding the timber endwise across the machine. By a baud wheel the mortising bar is raised or lowered to suit any point on the width of the timber : by a screw and hand wheel, the mortising bar is brought up to the timber and the square chisel forced through ; a hand lever performing for the auger the same function. The cross movement of the bed is controlled by a friction clutch having steps to gauge the length of the mortise. The chisel mandrel is driven by a friction gearing with a quick return ; and there arc suitable stops for gauging the travel of the slide ; also a regulating screw for changing the position of the chisel to suit the work. An extra boring attachment is fitted to the machine for boring joint bolt holes. side and general work.
The Ryan Hub Hortiner and Borer, shown in Fig. 3, has a single chisel bar with vertical stroke, the amount. of which may be varied by altering the angle at which the short connecting rod from the crank disk meets that from the upper end of the boring bar. The change in the stroke is accomplished by a treadle, and it is claimed for it that it prevents the slightest jar upon the foot even when mortising without first boring the hole to admit the chisel. The mortising chisel is reversible
on the Jack-in-the-box plan, so us to cut either end of the mortise square. The boring mandrel has vertical traverse and is eounterweighted ; it is driven by beveled gearing from a horizontal axis belted at the back. The reverse may be controlled by the operator at will, or it will work auto matically if set to do so. The boring bit is in line with the chisel, and there is a stop for gauging the depth of boring. The chuck for holding the hub is spaced to mortise for JO, 12, 14, 16, or 18 spokes, whether in line or staggering. One end of the hub is held by two jaws. parted by a right and left-hand screw. The other end of the hub rests in a cup of suitable size. The table has a lateral movement across the machine, parallel with the hub axis, the cross feed being given by a hand wheel.
An automatic double-chisel hub-mortising machine, St meted for mortising or re-mortising hubs from 6 to 16.1 in. in diameter, and cutting mortises in hard wood up to 2i in. wide and 8t in. long, either straight or staggered. ln operation, the table carrying the hub is lifted to the chisels until the full depth of cut is reached, and remains stationary until the mortise is complete, when it descends, the hub turning one notch of an index plate, ready for the next mortise. The gigging. spacing, feeding, etc., arc automatic, The capacity is 75 to 80 hubs per hour. The operator starts either the boring or the mortising bar, as desired, by a friction gear and treadle. lit relieving the friction an automatic brake is applied, stopping the machine at once.
_Mortising Some mortising machines for sash work have the disadvantage of not cut ting for the ends of the pulley flanges, and of not cutting and rebating, long enough for them to allow the screw to enter the wood without splitting.
A mortising c h i sel, Fig. 4, which is especially adapted for drawing from the work the chips that it produces, has extending down its back, upon the side which bears the bevel, a thin rib at right angles to the blade of the chisel ; and from this rib there project a number of small barbed lips which serve to draw the chips from the hole.
A chisel for mortising in sash pulleys, shown in Fig. 5, consists of two chisels, each of which has a cutting edge of L section, and both of which operate at once, one of them cutting in advance of the other about half the stroke of the chisel bar ; then• cutting edges being placed so as to face in the sante direction. The longer of the two chisels of course cuts first, mortising clear through the pulley stile, and the short one, which is wider than the other, mortises for the flange of the pulley at the same time, thus finishing the pulley in one handling.