Installing concealed hinges can be a pretty simple process, even using a hand held drill, with the help of a jig. The Rockler Concealed Hinge JIG works really well at positioning the Forstner bit, as well as holding it square to the door frame surface and finally controlling the depth of the hole. Of course, if you have a drill press with a good fence and large enough table then that will work just as well.
The first step is to mark the center line of where the hinge will be positioned. Then position the jig using the alignment arrows and clamp it in place. Note: the clamp is on the underside, or show face of the door. You can’t see it in the following picture and I didn’t take a picture showing it. Sorry, my bad.
Set the stop collar on the bit guide so the bit drills to the correct depth. I like to drill a test hole in a scrap piece of wood and make sure the hole is deep enough to allow the hinge to fit in without bottoming out.
The bit guide is then positioned over the alignment plate. The wide circumference of the bit guide ensures that the bit is held square to the work surface, important when drilling with a large Forstner bit. As the bit guide fits over the alignment plate it also stops the bit from wandering.
After placing the hinge in the hole, check that the back of the hinge is parallel to the frame using a square.
Use a self centering bit to drill pilot holes for the hinge screws.
