Photo 7- The hinge template in use. The wood part is clamped to the template fence with the template resting on top of the wood part, then the router is pushed along on top with the template guide riding along the edge of the template.

With the fence secured to the template the jig is now ready to use (photo 7). Clamp it in place with a test piece and set up the template guide in the router base. I used a 1/2" guide and a 1/4" bit. The minimal bit diameter was important to keep the corner radii to a minimum on these small mortises. The disadvantage here was that the bit chattered some if I pushed it too fast, and that can make an uneven mortise edge which looks bad against a straight metal piece. So I cut slowly. Template guides can be troublesome if they are not well centered to the bit, thus causing the mortise to be offset from the template. In order to center the bit, I have occasionally put masking tape between the router motor and base to shim the motor shaft toward center. But usually I just hold the router so that the off-center bit points away from areas where it might cut too deeply. Thus I had 1/8th inch plus 1/64th or so between my hinges and the part rear faces instead of exactly 1/8th inch. The trick here is to duplicate the error exactly on both door and frame mortises so that both are equal.

Photo 8A- Cutting out the lock box portion of the lock mortise.

Another, more accurate way to deal with the centering problem is to use an overhead bearing flush trimmer to cut the mortises, rather than a template guide mounted in the base. These are never offset from their bearing. To do so you will need to use plywood template stock at least 1/2" thick. But I have found template guides to be accurate enough most of the time.

Photo 8B- Blowup of the result of the operation shown in photo 8A.

The lock mortise is made with three separate cutting operations using two jigs (photos 8 thru 10). I first cut out the deeper, smaller hole for the lock box (photo 8) and then locate the two shallower, larger cuts by locating that jig in reference to the first cut (photos 9 and 10). You could do the shallow ones first just as easily. Both shallow cuts are made using the same jig because the height is the same for both, only the width and depth change, and both of these are easy enough to change that there is no need to make a third jig. After the first shallow cut is made on the door inside face (photo 9), the jig is then set up on the edge with a spacer between the fence and door (photo 10). The width of the inside face mortise was 3/4" and the width of the edge mortise needed to be 3/8", so with a 3/8" spacer the difference was easily taken up. Carefully align the heights of the two cuts before making the edge cut.

Photo 9A- The shallow cut for the lock plate.

I made the depth of cut on the edge deeper than the rear face cut even though the thickness of the cast brass plate on the lock is the same in both locations. This insets the lock slightly to allow for fitting the door and sanding later. If you do this remember that the width of the rear face mortise must be greater to compensate.

Photo 9B- Blowup of photo 9A. Only the shallow cuts on either side were made in this cut, the deeper center part was cut in the first operation shown in photos 8A and 8B.

Cutting the mortise for the ball strike will be done last of all, after the door is finally fitted. The relation between the ball and strike must be carefully set up to ensure that the ball holds the door shut correctly, and I prefer to do this individually on each cabinet after the door is fitted. Also, while the frame hinge mortises can be cut before the frame is even glued up, the door mortises shouldn't be cut until after the door is exactly fitted to ensure proper clearances at the door top and bottom. Don't do the door mortises first and the frame mortises later, because you can't get the router any closer to inside frame corners than the radius of your router base.

Photo 10A- The third cut for the lock, this time on the part edge. This cut is as long and about as deep as the last cut (photos 9A and B), but not as wide. A spacer beween the fence and the part reduces the width.

It took only a few hours to make all the templates, and cut out all the mortises for the hinges and locks. There will be a few more hours total to square the corners and do final fitting. A while ago I fitted similar hardware for two cabinets by hand, and reviewing my time sheets I see that it took about the same time to do two sets by hand as it took to do five by production. I also see by the sheets that I used exactly the same hardware. Drat! Why didn't I make the jigs then?

Photo 10B- Blowup of 10A. Note the thin spacer between the fence and work.

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