small mortise hinge jig for boxes etc.

I've been struggling with fitting brass hinges into softer woods that I seem to work with today against my better judgment.
By the time I have the mortise cut for the hinge I find that usually a portion of the mortise has either fallen away, been crushed by my chisels, or a combination of both leaving an unsightly gash into which I have to place my hinge.
I've been looking at this jig as outlined in ShopNotes volume #12 No. 74.

From hinge jig

From hinge jig

From hinge jig

From hinge jig

The principle of this jig relies upon your router having a square base with exact sides. In my case I am waiting for a new router and used my roto zip that happens to have a 4 inch base attached from a previous job.

From hinge jig

The first thing you need to do is determine where you need your hinge to sit in the wood. I laid a couple of hinges up as shown and marked their positions with a sharp pencil.

From hinge jig

Next I opened the gate on the jig and fitted each hinge to the exact opening. Next the depth of the hinge was set using a side gauge on the jig.

From hinge jig

Once the frame is lined up with the dimensions of the hinge the depth of cut is set for the router bit to match the thickness of the brass hinge being used. I actually made the mortise inset slightly deeper than the hinge so I could lightly sand away the milled edges giving me a cleaner mortise .
The last picture pretty much speaks for itself.
As shown, a 2 1/4 inch mortise on the left and the three-quarter inch mortise on the right and both are more than acceptable by my standards.

From hinge jig

You canwatch a demo of this jig here:
http://www.shopnotes.com/issues/74/videos/using-the-hinge-mortising-jig/