In some planing machine tables a V-groove is cut along the centre for the purpose of holding spindles to have featherways or splines cut in them, the method of chucking being shown in [Fig. 1619]. This, however, is not a good plan, as the bolts and plates are apt to bend the shaft out of straight, so that the groove cut in the work will not be straight when the spindle is removed from the clamp pressure. The proper method of chucking such work will, however, be given in connection with [examples on planer work].
For the round holes in planer tables several kinds of plugs or stops are employed, the simplest of them being a plain cylindrical plug or stop.
Fig. 1620.
[Fig. 1620] represents a stop provided with a screw b. The stem a fits into the round holes, and the screw is operated to press against the work. By placing the screw at an angle, as shown, its pressure tends to force the work down upon the planer table.
Fig. 1621.
A similar stop, termed a bunter screw, s, [Fig. 1621], may be used in the longitudinal slots, the shape of its hook enabling it to be readily inserted and removed from the slot. These screws may be applied direct to the work when the circumstances will permit, or a wedge w may be interposed between the screw and the work, as shown.