The Powermatic TJ Tenoning Jig has a unique feature; you can use the cutting tool you cut the mortise with to set up the jig and dial in the resulting tenon. Seems like a great idea. Does it work? Let’s find out.
The guide bar is designed for 3/8” x 3/4″ slots. The fit can be fine-tuned, and access to do the fine tuning is done from above. I love that. Adjusting from above means the tenon jig can be in place on your saw and you can finesse the bar without removing, adjusting, testing, removing, adjusting, testing… You get the picture. The guide bar also allows adjustment (again, from above) to ensure the jig is parallel to the saw blade.
The guide bar can go in one of two positions; one if it’s 5” or more from the blade to the miter slot. The other if it’s less than 5” from the blade to the slot. That means the jig should work on full size and benchtop table saws.
This is the unique feature of the Powermatic Tenon Jig. Sandwich the cutting tool between blocks #1 and 2, and the material the tenon will be cut into between block 2 and the fence, and you should be good to go on tenon size. The video above demonstrates this process. I was amazed by how well this feature worked. The first cut I made using this set up produced a perfectly fitting tenon. This is a great feature.
Fine tuning the size of the tenon is easy, and can be done using the micro adjust knob. This makes it very easy to finesse the tenon size. One full revolution of the micro adjust knob moves the fence about 1/64”, making it easy to dial in a perfectly fitted tenon.
The Vernier scale makes it very easy to track the changes you’re making using the micro adjust knob.
The work stop (vertical fence) can be adjusted up to 45-degrees for angled tenons. The clamp is easy to manipulate for different sizes of material, and does a great job of securing parts to the jig.
This is a very well thought out tenon jig. I’m amazed by how well the tenon preset function works. This really simplifies getting a good fit between the tenon and mortise. Add to that the ease of micro adjusting the jig, and I found there was zero frustration in achieving the exact fit I needed. If table saw tenons are on your to-do list, I’d strongly recommend this tenon jig.
Powermatic PM-TJ tenon jig