The wrong size accessory. Hi, This is my first posting to this site. USE ONLY DRILL BITS, CUTTING TOOLS, OR OTHER. Here's a link to an article by Jim McCormac. Keep chisel and drill bits The workpiece should be moved so that the slot in the chisel is releasing chips into the already 2 Bit protrusion of 1/16” is. . Meichoon 3 Pcs Mortise Chisel & Bits Woodworker Square Hole Drill Bits Mortising Slot diameter: 1/4 inches (mm), 3/8 inches Mortiser Drill Bit 1/4. If ya wanna know details let me know. ACCESSORIES with shank size recommended in your instruction manual. I'm sad to report a blight is ravaging our native stands of American Beech here in the Midwest. High Speed Steel (HSS) Long Slot Mortise Router Bits are mainly suitable for use on: Slot Mortise Machine (Oscillation Mortiser Machine); Machining Centres. I thought I'd show (off) my slot mortiser. Mortiser Drill Bit Tool Set 【6 Different Slot Diameters】: 6 pieces square hole drill bits mortising machine or a mortising attachment; Fits all mortising.