While surfing around the woodworking sites, I found mention of this jig for cutting mortises. It’s a Mortise Pal (mortisepal.com). If you have a plunge router (weighing less than 12 pounds), a 5/8″ outside-diameter bushing and an upcut router bit, you can create mortises for mortise-and-tenon joints and loose-tenon joinery using a Mortise Pal.
To use a Mortise Pal you need a 6″ base on your router. If you use a smaller base, due to the jig’s design, the base could slip off one side resulting in a bad mortise (the router rides on top of the side supports). Also, pay attention if your router’s base is something other than round. As for weight, 12 pounds pretty much restricts you to a 2-1/4 hp router or smaller, so don’t try to hoist up that 3+hp hog and cut mortises.
And of course, an upcut router bit is best because it pulls waste from the mortise and the cut will be easier to make, and cleaner when finished.
Any stock in which you want to cut a mortise in the end can be a minimum of 1″ in width. Stock thickness can be from 2″ to 3/4″ (you can mortise thinner stock by arranging shims as shown in the manual, which you can download off the web site or below). The mortise length is determined by the mortising templates (four sizes are included in the kit) and the router bit size (a maximum 1/2″ due to what fits through the bushing). Changing the templates is a snap and locking them into position is both secure and reliable with each change.
Layouts for mortises you cut with the Mortise Pal are different from the method most of us are accustomed to using. For this tool, find the center of your desired mortise along both length and width, then use the engraved line and small pointer on the jig to set up the cut. Once you’ve dialed into your lines, lock the brass thumbscrew, twist the lock knob to secure and you’re ready to work. (To watch a Mortise Pal in action, click here.)
I don’t cut mortises with a router most times; I have a mortise machine for that task. But, if you don’t have a dedicated mortise tool, a Mortise Pal is a good choice. (Hand-tool Neanderthals take a breath, please.) One area that always bothered me when building furniture was when I mitered a base frame on a chest of drawers or other case piece. I often chose to use a biscuit joiner for the connection. Because the Mortise Pal fits the workpiece, especially if the piece is mitered, I see using the Mortise Pal there for a simple loose tenon connection, resulting in a strong joint.
Bottom line: the Mortise Pal is well-machined tool that works. I think it’s a bit pricy at $189, but the Mortise Pal has CNC machined anodized aluminum parts along with stainless steel parts, and the templates are polycarbonate. In my opinion, there was no skimping on manufacturing. Also, if you buy a dedicated mortise machine, you’ll spend more and not have the mobility or range of uses you have with this tool. And, you’ll get the job completed quicker than if you hog out material at a drill press, then clean up the mortise with your chisel.
Here’s a tip for routing mortises. Plunge the mortise area first, then slide the router along the cut to clean out and remove any left-behind waste material. I plunge the ends of the mortise then move to the center before clearing the cut. This may be old news for you, but I picked up the process just a little while back , there is always something new to learn while woodworking.