Simple Juice Groove Jig for Cutting Boards

So you make a bunch of cutting boards, mostly of approximately the same size, but not quite identical. How do you cut a juice groove consistently 1” or 3/4" from the edge? With a custom adjustable juice groove jig. Here is how!

Supplies

1/2" or 3/4" plywood or MDF

Wood Glue, CA Glue

Threaded Inserts for Wood (1/4"-20)

1/4"-20 threaded screw knobs

Table Saw, Router

Step 1: Cut the Frame Pieces

I used 1/2" birch plywood, but 3/4" plywood or MDF will also work. A 2 foot by 2 foot sheet will suffice for making the jig. All dimensions shown are for my Bosch Colt Palm Router with a 4” diameter base plate; and 1/2” plywood. The dimension will result in a groove that is centered 1 inch from the edge of the cutting board. Adjust for your specific needs.

Cut plywood strips to the following dimensions, as shown in the attached 'Juice Groove Jig.pdf':

2x 2” by 24”

2x 2” by 19”

2x 1.5” by 23”

2x 1.5 by 18”

4x 2" by 2”

On the 2” wide pieces cut a center slot with a 1/4” bit, 1” from top/bottom as shown in the drawing. Then widen the slot slightly to make the jig adjustment a little easier during use. Glue the small 2" by 2" plywood rectangles to the end of the strips as shown. This will allow you to install a threaded insert for the adjustment knobs.

Step 2: Glue the Frame Brackets

Glue/screw two plywood strips together to form an angled bracket as shown. The slotted piece is 1" longer as it should overlap the adjacent bracket in the final jig. Make two brackets that are 24” long, and two that are 19” long. Check the pdf drawing for reference.

Step 3: Install Threaded Inserts

Drill a 3/8” hole into the end with the 2" by 2" piece, countersink, and install the threaded insert. Use one of the slotted bracket pieces to mark the hole at the right height, it should be 1.5" up. Also, before drilling I strengthen the plywood end by soaking it generously with thin CA glue and letting it dry.

Step 4: Knobs

Make or buy four knobs with 1/4”-20 threaded bolts. I 3d-printed the knobs, the stl file is attached. The bolts are 1/4”-20 and 2“ long.

Step 5: How to Use the Jig

To use the jig arrange the four brackets around the cutting board and tighten the knobs. This will hold the cutting board in place and give you a frame to guide the router. Clamp the jig to a workbench. Make several router cuts at increasing depth. Move the router in a clockwise direction while pushing firmly against the brackets. (Mark the jig for future reference to remind you of the routing direction!) Make a final very light cut to clean the groove.

Success!

If you wish to have the groove closer to the edge you can insert spacers between the cutting board and the bracket frame.

When you are done you can take the jig apart; it takes up very little space for storage!