Locking Table Saw Fence Homemade Machines & Jigs
Over the years since building my table saw fence, I’ve occasionally been asked if it deflects sideways when using it. This question is based on how the fence works – it locks on the front rail only and the back end of the fence isn’t secured in any way. Simply put, if it was doing that to any amount that would cause a problem, I’d stop using it. Fact is it can move if you push it hard enough. But under normal usage, you shouldn’t be pushing on it enough for that to happen.
But, these questions did get me thinking about designing a version that does lock on the back as well as the front. Not that I hadn’t before – I’ve made fences like that, but nothing that was self squaring with a cam handle. Those are the features of my first version of table saw fence that make it such a pleasure to use and I’d want to have the same on a new version.
As always the project gets started by cutting the parts as shown in the plans. I’m using Baltic birch plywood, but any good quality cabinet grade plywood will do. I’m ahead of the game on mine, though, since I already have the fence rail and support made and mounted on my homemade table saw. The fence rail is the same as the one for the original version.
The build video recaps how the fence rail and support were made and installed on the saw:
For this fence system, the fence rail needs to be securely fastened to the fence rail support and parallel to the back edge of the table saw top. If the back edge of the top is irregular, you’ll have to mount a rail on that edge that’s straight and parallel for the fence to lock against. It also needs to be square to the blade and miter slots on the saw. This is the cost of having the fence lock on the back – it the front and back aren’t parallel, the fence won’t work as designed.
If this is difficult to do on your saw, I suggest going with my previous design. It is more adaptable to these conditions.
So with the fence rail already done, I just had to cut out the parts for the fence itself. These parts make up the tee and the core of the fence (missing are the two fence faces):
I show the assembly in more detail in the build video, so be sure to watch that. Here are two main subassemblies of the fence – the tee and the fence base. I used scraps of plywood wedged in the miter slot to put the fence base against and wedged the tee tight against the fence rail to hold it in place:
The fence base is made 1/8″ (3mm) short of the top plus fence rail total length to give a gap on the back and the front. The gap allows the metal clamping plates to clamp onto the back and front of the saw:
The gap at the front:
And the tee is centered on the fence base and wedged in place against the back of the fence rail:
The two subassemblies are then glued together and lightly clamped front and back. I left it to dry while I worked on other parts, then drove in two 2″ screws (as shown in the build video) to reinforce the joint:
Probably the most difficult part to make is the cam handle, but if you are careful it’s hard to mess it up badly enough where it won’t work. A cam needs an offset from the pivot point to work properly and for this one it’s 1/16″ (1.5mm). The cam center point is for the outside of the cam that you’ll cut on the band saw or jigsaw, while the bearing center point is drilled out with a bit that matches the size of the bearings used:
After carefully laying out one, I used it as a template to cut out the other one. I fastened the layers with double sided tape and pin nails for insurance and drilled the bearing holes in both at the same time:
I also sanded them as a pair before taking them apart, ensuring that they are both exactly the same.
These thin wooden tabs keep the bearings in place. They are glued on the inside. Also the handle should be made to come apart with screws through one of the handle halves into the spacer:
Another tricky operation is drilling the hole for the threaded rod through the pivot pin. I did that on my drill press and used a V block. The hole should be as centered as possible, but don’t get hung up on Nasa precision – it just has to be close:
More metal work, the clamping plates are fairly simple. I recommend using 1/4″ (6mm) thick steel or aluminum, but 1/8″ (3mm) will do if you double it. You’ll only have to use two layers on the front, though:
These plates are screwed to the sub top. The one on the back has the screw fully driven, while the screw on the front is slacked off slightly to allow the plates to move. With the top glued to the sub top it’s set on the spacer blocks on the fence base. These subassemblies are not fastened together here – the top assembly still need to be adjusted forward or back and that happens in the next step:
With the threaded rod put in, the pivot pin is bolted to the front end with two nuts. The cam handle is assembled around the pivot pin with the bearings in place:
The fence tee is once again wedged tight against the back of the fence rail:
And the cam handle is pushed all the way in with the handle standing up:
Then rotate the handle down 90 degrees and make sure the locking plate(s) is tight to the fence rail:
The nuts at the back can then be threaded on and tightened. You’ll use these to adjust the fence clamping action and having two nuts tightened against each other stops them from loosening:
With that alignment made the faces of the fence can be clamped on and fastened with screws. While these can be glued, I recommend just using screws – 8 of them in each face:
After the fence is done you need to check to make sure it’s square to the table saw top:
You can adjust it by shimming one side of the tee with a thin slice of wood glued on:
The squareness to the table saw top can be adjusted in the same way, by gluing a shim on one side the vertical part of the tee. We are woodworkers, after all!
I also glued a thin shim at the back on the bottom to lift the fence off the table saw top slightly. This lets it slide much easier:
And it’s finished. I gave mine three coats of water-based polyurethane to protect it and keep it clean:
Plans are available if you’d like to build one for your saw: