Mortice Lock Jig Guide: Fit Door Locks Fast and Square
A mortice lock jig takes the guesswork out of one of the trickiest cuts on a door install — the lockset mortice. Instead of chiselling out a pocket by eye and hoping the strike plate lines up, you clamp a template to the door edge and let the router do the precision work. For a carpenter fitting locks across 5+ doors a day, that's the difference between a clean, fast job and a re-cut jamb.
What Is a Mortice Lock Jig and Why It Matters
A mortice lock jig is a router template that sets the exact position, depth, and width of a lockset pocket before you make a single cut. Clamp it to the door edge, run a plunge router around the guide bushing, and the pocket comes out identical every time.
Compare that to chiselling by hand. Depth varies cut to cut. Hardwood doors split if the grain runs the wrong way under the chisel. Strike plates end up proud or recessed because the mortice isn't square. And every mistake costs time — either packing out a loose plate or re-cutting the jamb to fix a misaligned lock.
This isn't a tool-features issue. It's an outcomes issue. A lock that's cut square doesn't rattle, doesn't bind, and doesn't come back as a callback. On a job where you're fitting locks across a whole build, one bad mortice is a rework; a jig means every door gets the same result, first time.
How Does a Mortice Lock Jig Work?
The jig clamps to the door edge at a set height, referencing off the door face so it's square every time. A guide bushing — matched to your router bit size — traces the inside edge of the template opening while the plunge router cuts.
The router makes fixed passes: the lock body pocket first, then the spindle hole and latch face. A depth stop on the router controls how far it plunges, so the pocket depth matches your lock body exactly — no measuring by eye, no test-fitting the lock three times before it sits flush. Because the template controls both position and depth, the same setup produces the same cut on door two, door ten, and door fifty.
How to Fit a Lock with a Mortice Lock Jig, Step by Step
Here's the process, start to finish:
- Mark the centre line for the lock at the height specified on your door schedule.
- Clamp the jig to the door edge, aligned to your mark and square to the face.
- Rout the lock body pocket, plunging in stages to full depth.
- Rout the spindle hole and latch face using the same template setup.
- Repeat on the jamb for the strike plate, using the matching jamb template so the strike lines up first time.
Five steps, no chiselling, no test-fits. The table below shows why that matters against the two other common methods:
| Method | Time per door | Consistency | Risk of splitting/misalignment | Tools required |
|---|---|---|---|---|
| Mortice lock jig | 2–3 min | Identical every door | Low — template controls position and depth | Plunge router, jig, matched bit |
| Freehand chiselling | 15–20 min | Varies with skill and fatigue | High — hand control, grain tear-out | Chisel, mallet, marking gauge |
| Drill-only method | 8–12 min | Moderate — depth still eyeballed | Moderate — round holes need cleanup for square lock bodies | Drill, spade bit, chisel for cleanup |
The time difference alone pays for itself inside a single day of lock fitting. The consistency is what stops the callbacks.
The Fast Hinge Hinge and Latch Combo Kit
Most carpenters end up juggling separate jigs for hinges, latches, and locks — each with its own reference points, which means re-measuring every time you switch tasks. The Hinge and Latch Combo Kit fixes that. It's one system with matched templates for hinges, latches, and strike plates, so every cut on the door references the same line.
Built for job-site volume, not a one-off DIY project — it's the same system 13,000+ carpenters across Australia and New Zealand are already running, rated 4.9/5. The Hinge and Latch Combo Kit is $480 AUD, with free shipping on orders over $300 AUD. Shop the Hinge and Latch Combo Kit →
Note: this kit is currently on preorder, shipping approximately 20 August 2026 — order now to lock in your spot for dispatch.
Frequently Asked Questions
What size mortice lock jig do I need for standard Australian doors?
Most Australian residential and commercial doors use 85mm or 100mm hinge spacing, and standard mortice locksets are sized to match. The Fast Hinge Hinge and Latch Combo Kit templates are built around these standard Australian sizes, so you don't need a separate jig for each door type on a typical job.
Can a mortice lock jig be used with any router?
Yes, provided your router accepts a guide bushing matched to the jig's bit size and can plunge to the required lock body depth. A standard cordless or corded plunge router with a 6.35mm or 8mm collet will handle most mortice lock jigs, including the Fast Hinge system.
Does the same jig system handle both hinges and locks?
With the Fast Hinge Hinge and Latch Combo Kit, yes. Hinge, latch, and lock templates share the same reference points, so you set up once and cut hinges, latches, and strike plates without re-measuring for each component.
Ready to Speed Up Your Installs?
Stop chiselling locks by eye — the Hinge and Latch Combo Kit gives you matched templates for hinges, latches and strike plates in one system, so every door gets the same clean, professional result.
Hinge and Latch Combo Kit — $480 AUD
Shop Hinge and Latch Combo Kit →
Free shipping on orders over $300 AUD | 4.9/5 from 13,000+ carpenters