What steered me away from the Router Boss and it's English equivalent is that, when making multiple cuts, like you would when doing dovetails, you are depending on pencil marks for positional accuracy between each pin and dovetail being cut. This holds true for any type of joint being multiple cut using this type of tool. The Router Boss is well made, but to me, it can't be as accurate as I would want due to this "positioning to pencil mark" requirement . I've watched several demonstrations of the Router Boss before coming away with this conclusion, and I ended up buying the Leigh D4R dovetail jig because the tails and pin widths and their positions are determined by the same position adjustment of the jig fingers. Set one and the other follows.
For mortise and tenon joints I watched several demonstrations of the Multi Router, I once owned a Trend M&T jig (not at all happy with it), and I had considered a Mortise Pal and other floating tenon methods.
To me, the Panto Router is very similar to a Multi Router in the way that it works. A pin follows a ready made pattern with no tolerance adjustment. There is also a Wurth machine and a similar, but cheaper version of a Multi Router being sold by Woodworkers Supply. All work about the same. In all of these you follow the edge of a pattern to cut a tenon and then set up stops to cut the matching mortise. No tolerance adjustment exists for getting a perfect tenon to mortise fit in any of these. In one demonstration that I watched the demonstrator wrapped the tenon pattern with one layer of Scotch Tape in order to increase the tenon size so the cut tenon would be a little larger to fit it's mating mortise, and the mortise size was dependent on the size accuracy of the bit used along with the way that the operator proceeded to plunge the bit into the wood. It fit, but to me it wasn't to the quality and repeatability that I was looking for.
The Leigh FMT jig can cut both the tenon and it's matching mortise with the same set up, and only the Leigh FMT provides an adjustment for fine tuning the size of the tenon to perfectly fit the matching mortise. I could find no such fine tuning adjustment in any of these other tools. I've now owned a Leigh FMT Pro jig for about 12 years, along with all of the bits and all of the patterns for Imperial sizes to use with it. It saved my back side when I took a job that required making just over 1,600 M&T joints. It paid for itself on that one job and has been in my tool arsenal ever since. I watched the Leigh demonstration at a wood show many times and asked questions of the demonstrators before buying it until I became convinced that I had to have one.
At the show they cut a tiny tenon on the end of a wooden match, and then cut a through mortise in a second wooden match that the tenon fit perfectly into. That and their display of other M&T joints that had been cut, totally convinced me that I had to have an FMT jig.
The fine tuning adjustment on the FMT is a slightly tapered pin with an adjustment knob for setting it's height. This pin rides around the outside of the pattern to cut the tenon and in a slot in the middle of the pattern to cut the matching mortise. By adjusting the pin's height, you can slightly change the size of the mortise and the matching tenon in order to achieve a perfect fit between them, and this fit is accurate and repeatable to thousandths of an inch. Once the fit is correct, you can crank out perfect fitting mortises and matching tenons of that size all day long. They can be loose for needed glue space or POP like a pop gun when dry fit and you pull them apart. Every mortise and tenon cut with those settings will be the same and to that accuracy. The settings can also be recorded so you can repeat the result using the same bit and tapered pin height and get the same results a week or month later.
I'm just a very satisfied Leigh customer. I have no connection to them otherwise.
Watch the YouTube demonstrations for each tool closely to see how they make fine adjustments for fit. Then watch the Leigh D4R and FMT demonstrations. A personal demonstration of each of these tools would be better, but once educated in what to look for, I think you will be able to see the limitations of each tool.
Central North Carolina
Last edited by CharleyL; 11-23-2018 at 07:35 PM.