If you make a lot of picture frames, cabinet doors and drawers, or decorative boxes, you know how important (and sometimes time consuming) it is to ensure every corner is dead-on square. A squaring jig can be used to make it easier and quicker to glue up your work pieces by providing a reliable reference point and holding the material securely in a perfectly square position, eliminating the need for manual measurements. These squaring jig plans are for a 24″ x 18″ jig, accommodating work pieces up to 21″ x 16″, and the built-in tape measures also provide a quick reference to ensure your moving fence is parallel to the opposite fixed fence. You can easily alter these plan to allow for a larger pieces by just enlarging the base and rails.

To use the squaring jig, simply set your workpiece in place referenced to the corner of the fixed rails, slide the moveable rail so that it is tight to the workpiece and square to the other rails, then tighten the knobs to lock it in position. Finally, use some bar clamps to clamp the open end of the workpiece to the rear rail of the jig.

Materials Needed

• 2 – 3/4″ plywood at 24″ x 18″ (base plate)
• 1 – 1 1/2″ x 1 1/2″ x 24″ hardwood maple (rear rail)
• 2 – 1 1/2″ x 1 1/2″ x 16 1/2″ hardwood maple (side rails)
• 2 – 24″ t-track
• 2 – t-track bolts and knobs
• 2 – Left to Right adhesive tape measures (optional)
• 3/4″ wood screws
• 2″ wood screws
• wood glue

Tools Needed

• Table saw
• 3/4″ dado stack or Router and 3/4″ straight bit
• Tape measure
• Drill / Driver with countersink bit
• 1/4″ drill bit
• Square
• Brad nailer
• Socket wrench set

Step 1: Make the plywood base

The base of these squaring jig plans is made out of two pieces of 3/4″ plywood, both cut to 24″ x 18″. For the top piece, you will need to cut two slots, 3/4″ wide x 3/8″ deep. I like to have the front slot inset 2″ from the front edge, and the back slot inset 2″ from the face of the rear rail.

If you are going to add the measuring tape, then depending on the thickness and width of the one you purchased, you may want to add another shallow rabbet next to both of these slots to accommodate the tape measure. That way it won’t be protruding from the face of the squaring jig and the moveable rail will be able to glide easier.

Use lots of wood glue between the two pieces of plywood, and the 3/4″ wood screws to screw in the t-track. This should hold the base together until we add the rails.

Step 2: Add the hardwood rails

All three rails are made from 1 1/2″ x 1 1/2″ hardwood stock (I recommend maple). The rear rail is cut to 24″ and is attached to the base using 2″ wood screws. Use your countersink bit to pre-drill the holes from the underside of the base. The rear rail needs to be 100% parallel to the slots you cut on the top of the base, so it should maintain an equal 2″ distance from the t-track the entire length of the rail.

The left side rail is fixed in position as well, also glued and attached using 2″ wood screws from underneath. This rail needs to be at a perfect 90° angle from the rear rail. Use your square, and take your time squaring this up, as any deviation from 90° will be reflected in everything you make with this jig going forward. This is the most critical step in building this squaring jig.

The right rail is the moveable rail. You’ll need to drill two holes in this rail to correspond with the centers of your t-track for the t-track bolts to fit through. If your slots are 2″ from the face or the rear rail, and 2″ from the front of the jig, then both of these holes will need to be drilled 2 3/8″ from the ends of the rail.

Now, you just need to insert the t-track bolts, screw on the handles, and this squaring jig is ready to go! You should be able to easily slide the moveable rail tight against your workpiece, and the built-in tape measures should allow you to easily ensure the measurements are the same in the front and back of the workpiece.

I hope you enjoy these plans and find them useful. Please check out our other jig and workshop plans. If you have any questions, leave us a comment below. And don’t forget to submit your build if you use these or any of our plans to build something of your own.

* This post may have affiliate links, which means I may receive commissions if you choose to purchase through links I provide (at no extra cost to you). As an Amazon Associate I earn from qualifying purchases. Thank you for supporting the work I put into this site.