Double-Duty Trim Router Jig

By Jerry  “Jake” Seabaugh

Photos by author

Posted June 21, 2011

   
Trim routers are great for small operations. I wanted to make some precisely fitting holes for flower pots, but the circle cutting jig for my full-size router was too big. So I decided to make a small version for my trim router. Additionally, I wasn’t thrilled about the fence that came with my trim router, and wanted something that worked better.

How about a jig that had both a circle cutter and an adjustable fence for dadoes, grooves and flutings? This is what I came up with, and how to make it. 
 

Start with a piece of good 1/2” plywood. Make the base 7” x 18” with an over-size 1/4” slot cut down the center to accept a T-bolt. Add two guides 1” X 12-1/2”, spaced 3” apart. 
 

Mount the router base centered side to side and 3” from the front edge of the jig base and cut a hole for the bits to go through.

The circle cutter pivot pin is a 1/8” x 1-1/4” machine bolt, double-nutted with a star washer mounted in a 3” x 7” block. I positioned the bolt 1” back from the front edge. 
 

The pivot bolt is held in place with a counter sunk nut on the bottom. You also need to drill a 1/4” hole 3” back from the front edge to receive a 1/4” T-bolt.
 

The under side of the jig base is slotted to receive a 1/4” x 1-1/2” T bolt. Note that the bolts for the router base also must be counter sunk. 
 

The sliding fence is 7” x 7” and the sides are 1” x 7” so the fence will wrap around the jig base. Also note the oversize slot to receive the T bolt. 
 

Here is a top view of the circle cutter pivot pin block installed on the jig base.
 

The view from the under side shows how easy it is to set a radius to cut a circle.
 

This shows the under side of the jig with the fence installed instead of the pivot pin.

See how easy it is to set the placement of the fence for dadoes, grooves or flutes. 

The fence and the pivot block can both be mounted on the base for storage. A great way to make sure all the parts are there when you need them.