Mortise router base Jig

[Brian Knop]

Has anyone used one of these? If so what do you think. I know Rockler and Eagle america sell them.

[glenn bradley]

The issue I have with these jigs is that the closest you can get the mortise to the end of the board is the distance between the peg and your bit (which varies with material thickness). For example, the mortise cut in the picture on Rockler's page could not be done without the peg near the end of the board leaving the board's surface and hanging out is space. If you are steady enough to do that, who needs the jig.

To see what I mean, take a strip of paper about 1" wide and 6" long. Punch a hole in the middle and then a hole about 1-1/2" to either side. Let's say these holes are the closest peg positions. Position the paper on a board you want a mortise in so that there is a peg hole on either side of the board and you are as close to the end of the board as you can get without the peg hole leaving the boards surface. This is your starting/ending point for the mortise. If this is an acceptable minimum position for your work, you're all set. I wanted my mortise to start much closer to the end of the board.

[Brad Wood]

I suckered up and bought one.

Save your money.

I ended up making my own jig based on one David Marks used on one of his shows, with one small modification. I've got some other pictures if you are interested (like, showing the bottom). Just let me know. Works very well. only drawback I've found so far is you lose the amount of depth you can get from the bit by the thickness of the base. I'll probably do another one and use masonite. I think masonite will be rigid enough as long as all the other parts are the 1/2" MDF

[Vince Shriver]

I suckered up and bought one.

Save your money.

I ended up making my own jig based on one David Marks used on one of his shows, with one small modification. I've got some other pictures if you are interested (like, showing the bottom). Just let me know. Works very well. only drawback I've found so far is you lose the amount of depth you can get from the bit by the thickness of the base. I'll probably do another one and use masonite. I think masonite will be rigid enough as long as all the other parts are the 1/2" MDF

Brad, your jig looks very solid, adjustable and accurate. Why don't you post the other pics here; I'm sure other would like to see it also. Thanks, Vince

[Brad Wood]

okee dokee

I'm sure size can vary, but in this case...

Base is 16"x9"
The adjusters on top are 4.5"x9"
The bottom adjuster is 2"x16"

It is all 1/2" MDF, but like I mentioned, I'm thinking hardboard for the main base will work and will give more bit depth.

David Marks design had the bottom adjuster in a fixed position and he used shims to make adjustments to where he wanted the mortise on the piece. I made it an adjustable adjuster (LOL). Since the picture shown of the bottom, I've opened up the slots to allow for more range of motion.

Getting the left/right adjustment set, then the stops set, takes a little of testing first to understand nuances of the jig, I'd recommend doing a test piece like shown in the picture of the 4x4 post. Once you have everything set, repeatability on multiple pieces is cake.
Jig works great on horizontal work, or on vertical work (like shown)