How to Use a Door Hinge Jig: Step-by-Step Setup for Perfect Mortises

A door hinge jig clamps to the door edge and guides the router or drill, so each mortise matches the hinge leaf in size, depth, and position.

An off-center hinge mortise is a mistake you make once — patched door edges never quite disappear under paint. The setup that prevents it takes about ten minutes, and the order for how to use a door hinge jig barely changes from job to job: match the jig to the hinge, lock the jig to the door edge, then let the jig steer the cutter.

What does change is the hinge type. A full-size butt hinge needs a routed recess sized to its leaf. A concealed cabinet hinge needs a 35 mm cup drilled at an edge distance the hinge maker sets, which no jig can guess for you. Both runs are below, plus the limits that decide whether a jig fits the door in front of you.

Which Hinge Jig Fits Your Hinge And Door?

A jig has to match four things before clamping is worth the effort: hinge leaf size, hinge thickness, door thickness, and hinge style. Get one wrong and the jig still cuts a mortise — just not one your hinge fits.

Leaf size is the first check, since jigs are sold by the mortises they cut. Milescraft’s mortise kit line covers most of the common sizes:

The spread from $17.99 to $49.99 is small next to the cost of patching a door edge, so most people buy the model that covers their hinge leaf. Still comparing? Our tested roundup of door hinge jigs puts them side by side.

Two limits the price tag won’t show. A butt-hinge jig has edge stops but no 35 mm drill guide; a cabinet-hinge jig has a drill guide but nothing to register against a jamb. Door thickness matters too — a jig built for a 1-3/8 in. interior door won’t clamp a 1-3/4 in. exterior slab.

Setting Up A Door Hinge Jig On A Full-Size Butt Hinge

A full-size butt-hinge jig clamps to the door edge and locates the recess with edge stops and an end stop, and the router then follows the jig’s opening at a depth set just past the hinge thickness.

1. Identify the jig side or opening that matches the hinge size you’re cutting.
2. Stand the door on its edge with the hanging edge facing up, and block it so it cannot shift.
3. Set the jig against the door edge on its stops or pegs, then align the end stop with the top of the door or your marked hinge location.
4. Lock the jig down with its built-in clamping system or with clamps.
5. Fit the router with the guide bush and cutter the jig calls for, and set the plunge depth slightly deeper than the hinge thickness.
6. Rout the mortise, starting in a corner and working clockwise around the recess.
7. Square the corners if the jig or its manual says to, then test-fit a hinge leaf.

Depth is where this job goes wrong. Too deep and the leaf sinks below the door surface; too shallow and the hinge holds the door off the jamb. A test-fit leaf that drops in flush and doesn’t rock means the setup held.

Cutting 35 mm Concealed Hinges With A Kreg Jig

A concealed-hinge jig drills the 35 mm cup and the screw holes from a single clamped position, and its edge indexers have to be set to the distance your hinge manufacturer publishes — not to whatever looks centered. Kreg’s concealed hinge jig manual runs the sequence in this order:

1. Insert the 35 mm concealed-hinge bit into the drill guide and set the stop collar.
2. Turn the edge indexers to the cup edge distance the hinge manufacturer specifies.
3. Position the base against the hinge edge of the door and line up the top or bottom with the base scale or a marked centerline.
4. Clamp the base above and below the drill-guide socket.
5. Drill the 35 mm cup, then drill the screw holes through the guide holes.

The indexers are the step people rush. Set that distance wrong and the door reveal is off on every cabinet in the run. Done right, the cup presses in flush and the plate screws line up without forcing.

Every setup here comes back to the hinge’s own numbers: leaf size and leaf thickness for a butt hinge, cup diameter and edge distance for a concealed one. Pencil them on the door edge before you clamp anything, and the jig only has to do one job.