WoodSkills Issue 02 - Page 52

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A drill press bores 3/4 in. holes used for the ACME-threaded screws and nuts

In my design, these criteria received considerable thought and a 28-inch length was chosen. Since the Moxon vise is attached at the rear stabilizer block using holdfasts, a longer, notched rear jaw is eliminated. A longer, notched rear jaw would otherwise be clamped to the workbench using F-clamps. Clamping from the rear of the vise also provides a cleaner aesthetic. Next, holes are bored for the 3/4 in. ACME-threaded screws. Locations for drilling are marked on both boards. The 3/4-inch screw holes are located 3.5 in. from each end and 2.75 inches from the top. I recommend accurately marking the top and both faces of each board to avoid mistakes. Two holes in each 1.75 in. thick jaw are drilled. Each jaw is placed against the drill press fence and slid from side to side when drilling holes. The second jaw is placed against the same fence setting to ensure holes are precisely bored in both jaws. I insert a backer board between the workpiece and the drill press table. The backer board prevents blow out or splintering of the hole when the Forstner bit exits the bottom of the hole. A backer board is a sacrificial board that is flat and at least ΒΌ inch thick. The holes in the front jaw are slightly elongated on either side (1/16 in.) to allow for non-parallel jaw movement on irregular wood pieces.

After creating the 3/4 in. holes, I followed the Benchcrafted recommendation and elongated the holes about 1/16 in. on either side. It is critical to only elongate the holes from side to side and not from top to bottom. If the holes are instead elongated from top to bottom, the front jaw will not line up with the rear jaw and sit lower. After the 3/4 in. holes are precisely drilled to match the holes in the front jaw, the ACME-threaded screw and nut are temporarily installed in each hole of the rear jaw. Marking the mortise for the nut on the inner face of the rear jaw is next. With the screw locked with nuts on the inside and outside face of the rear jaw, I simply oriented the nut and marked its outline on the inside face of the rear jaw. The orientation of the six-sided nut is parallel to the jaw sides, as seen in the image. This step is repeated for both screw holes in the rear jaw. Since the six-sided nut is large, it makes sense to chuck a large Forstner bit (1 1/16 in.) into the drill press and remove as much wood waste as possible.