Cutting Driver Hole with Jasper 400 Jig

The Jasper 400 was mounted on a Ryobi RE175 plunge router using two of the pre-drilled mounting holes. From many of the reviews of this product, the following points are important to prevent cracking the base:

1. Do not over-tighten the mounting screws
2. The pivot hole must be perpendicular to wood surface, so the plate will sit flush on the wood.
3. No more than 1/8" deep cuts should be made in each pass to prevent stress at the pivot.
4. Use a dry lubricant on the pivot pin like Dupont No Stick.

This product which is not a production jig is made with acrylic, Plexiglas, not Lexan or a phenolic plastic and can be damaged unless care is taken.

Step by Step:

1. Determine the hole size and insert the pivot pin in the proper hole of the Jasper 400
2. At the center of the driver hole, drill a 1/8" hole at 90 degrees to the wood surface. Use a drill press, drill guide such as the Wolfcraft or a jig as shown below. (Note 1)
3. Set the plunge router for 1/8" deep cut.
4. Put a dry lubricant on the pin, Dupont No Stick.
5. Insert pin in pivot hole, plunge router and rotate router around pivot slowly
6. Continue these steps until driver hole is completed.

Note 1: It is critical to drill the pivot hole 90 deg to the surface. This can be done by using a drill press or a drill guide clamped to the surfase. A simple drill guide can be made by drilling a 1/8" hole in a piece of oak with a drill press or a guide such as the V-DrillGuide from Big Gator Tools can be purchased. See picture below.

Jasper Circle Jig mounted on Ryobi RE175 router.

V-DrillGuide from Big Gator Tools.