Step 1: Trace the Base

Remove the stock base from the router, then use a marker to trace around the base onto a 1/4" thick piece of clear acrylic. Trace the screw holes, but leave the protective coating on the acrylic (for now) to prevent the marker from smudging.

Step 2: Drill the Screw Holes

Use a drill press to drill holes through the marks made for screw holes. (Drilling through acrylic can be tricky; drill slowly to prevent the material from cracking.)

Use a countersink (chucked into a drill) to widen the top of each of the screw holes. Use the head of the actual screw that will be used in the hole to make sure the head countersinks into the hole.

Step 3: Make a Hole in the Center

Make a hole in the center of the base using a drill press equipped with a hole saw. To find the center, place the router on top of the acrylic, align it with the marks drawn on it and plunge down hard. This will make a mark on the protective coating to use as a center point for drilling the center hole.

Step 4: Cut the Base

Use a band saw to cut the shape of the base, and then remove the protective coating. Sand down any rough edges.

Tip: A set of hole saws allows you to create several bases with a variety of hole diameters. This is an easier way to create many specialized zero clearance bases.