JessEm’s Mitre Gauge Excels
By Rich Keller
Most mitre gauges that come with a table saw suffer from three major problems. First, the support surface for the workpiece is usually very limited. Second, often the bar doesn’t fit the table slot overly well. Third, the angle scale is usually not very accurate. Most mitre gauges can be set square with some effort and the use of a separate square, but a good mitre gauge should not take effort to make square and should not need the use of an additional tool. The overall accuracy is usually affected by all three of these problems, leaving the user with something less than usable. JessEm has addressed these three problems and more with their new mitre gauge.
The mitre gauge comes mostly assembled, and the little bit that has to be done is fairly simple. The instructions are quite good and lead you through what has to be done step by step. Assembly takes about 20 minutes. The gauge is adjustable for squareness and has a system of “snuggers” to keep the bar tight in the mitre slot and eliminate any play. Every table saw is a little bit different so the ability to adjust the gauge for squareness and fit in the mitre slot is important. Both the overall angle and the fence-to-table are adjustable for square. The length cut-off scale on the top of the gauge is also adjustable, so I can use the gauge to accurately cut pieces to length once set. JessEm provides a positive stop at 0°, 15°, 22.5°, 30° and 45°. The mechanism is solid and has no play in it. One of the first things I noticed when setting the angle is the laser engraved markings on the gauge. I also noticed that there is a vernier in 1/10o markings. This made me fairly confident when setting the gauge that I was getting exactly the angle I was looking for.
I was able to take the mitre gauge for a test drive on some angled chair tenons. In order to make angled tenons, a mitre gauge that can be changed both quickly and accurately is necessary. I cut a number of angled tenons and was pretty impressed. Cutting an angled tenon requires setting the gauge to one side of 90°, and then the same angle to the other side of 90° when the piece is flipped over. If the angle isn’t perfect, the shoulders of the tenons won’t be parallel and it won’t not fit tightly on one side when installed in the mortise. I was quite pleased that the shoulders were tight on both sides, meaning that the gauge had been set to the exact same angle for the cuts on both sides. Of course, if a tenon is slightly oversized, it can always be shaved with a hand tool, but I’m working on a set of eight chairs, with 24 mortises each, of which only four are square. That’s a total of 192 mortise and tenon joints. For obvious reasons it would be great to make 192 tenons that required little or no hand fitting.
Apart from my excitement at making 3o tenons quickly and painlessly, the JessEm mitre gauge certainly performs the more mundane and standard tasks of cutting boards square and to length well. The mitre gauge has a flip stop like most after-market mitre gauges, but this one is a little different from standard ones. The vertical face of the flip stop can be adjusted in and out from the aluminum cross fence to allow for the use of a sacrificial wood sub fence. Any wood up to 3/4″ thickness can be used, and the flip stop will be able to flip down properly and be tight to the fence face.
One problem I did encounter with the mitre gauge is that the washer on the end of the slot bar did not work with my table saw. It was too wide for my table saw’s T-slot. I ended up taking the washer off to be able to use the gauge. I don’t personally care for T-slot mitre gauges. I find them more of a nuisance than anything, so this was not a deal breaker for me. The idea behind them is that when cutting wider stock, you can pull the gauge back past the edge of the saw table and it won’t fall out. I never use a mitre gauge for wide stock and I prefer to be able to drop the gauge in the mitre slot anywhere on the table. But if you would like to use the T-slot feature of the gauge, double check to see that it works with your saw or possibly modify the washer to work.
Overall, I’m quite happy with the performance of the JessEm’s mitre gauge. Once set up, it’s quick and easy to set different odd angles and it has a good, long face to support the work properly and accurately during the cut. The gauge has a good feel in the hand and slides nicely on the saw once the bar “snuggers” are adjusted.