Yeah... yeah... thats the ticket !
Ok... here's a ton of "in use" pics. These were a demo test run.
Cant see the pencil marks well but step one is layout of the center of the mortise and the overall length. Note the top edge of the workpiece is flush with the top of the jig. I use the "base plate stops" to help index the workpiece.
When I made the jig I carefully marked the very center of the bit and extended those marks to the edges of the base plate. I line up these jig center marks with the center line mark for the mortise. Do this on each side using he base plate adjustment knobs to lock it down with its right on the mark. You have to set, adjust, set adjust a cpl times, going from each side of the jig base plate.
Next you lower the bit to the top of the work piece. Turn it so the "widest" part of the cutter is facing the edge... and slide the base plate until the edge of the bit is aligned with the end limit of the mortise. Tighten down the base plate travel stops. Do this on both sides.
Next set the depth of cut. I use a simple block to set the depth of cut at 3/4 inch.
Then its time to make the cut.
And the end product
Next is the cut in the end grain
Here it is set and clamped in the jig. This time the support bar acts as the clamp and there are two stops for quick indexing of multiple workpieces.
The set up is the same to make the cut in terms of alignment.
Here's the cut.
And the result
So.... thats it! Any questions, please feel free to ask !