Introduction: How to Install the Incra TS-LS Positioner

Hey Guys! This is my first Instructables post!

I just installed an Incra LS Positioner on my Ridgid R4512 Table Saw and I want to share the installation process with you. Inca was having a sale and I jumped at the chance. This table saw fence is incredible! By far the most accurate and versatile fence I have ever seen. So let dive into the installation process.

*Please use this post as just a guide.

Refer to the instruction manual for full details. One of the downfalls from ordering this fence from Incra is the shipping lead times which can be up to 9 WEEKS! I talk to one of the Incra reps and he said with the tariffs and high demand of the fence, the production lead times were stretched to the max. I guess that is a good problem to have. So, when you order, be patient. It's worth the wait. The shipment includes 2 boxes (at least mine did). One box for the rails and the other box contains the fence parts and hardware. Be warned, the boxes are quite heavy with the stacked aluminum inside. The instruction manual was one of the most well-written manuals I have ever seen. Each bag of screws and hardware where labeled and included in the steps in the manual. So you can easily reference the corresponding part numbers.


(1) 1/2 sheet of 3/4" plywood for extension wings (MDF or Melamine will work as well)

(1) Drill Set

(1) Socket set

(1) 32" Incra TS-LS Positioner Fence System

Step 1: Remove the Old Rails and Extension Wings

Removing the old fence from the R4512 is super easy. This fence is absolute garbage and I wouldn't wish it on my worst enemies. Remove all the bolts from the spacer rail, the rail bolts under the front of the table, at the back of the table, and the bolts holding the extension wings. (the bain of my existence) Good riddance!

Step 2: Clean Your Saw

This would be a good time to give the table saw a good cleaning. Use an air compressor or a can of air dust to blow off any sawdust. Wipe down the sides and table with some WD40. Also, this would be a good time to remove any rust from the top and recoat it with some GlideCoat

Step 3: Installing Rail Mounts

Take the rail mounts and attach them to the pre-existing bolt holes. You only need to use 2 mounts per side. Each mount attaches to the 2 end bolt holes of the cast iron top. The middle mount is not needed on the R4512. Only use the 3 mounts if your saw cast iron top is wider. (Grizzly, PowerMatic, Sawstop saws, ETC are usually wider) Space the mounts a 1/4" from the top. Once there are spaced properly. Tighten the bolts so it doesn't shift when installing the rails.

Pro Tip: There is absolutely no need to drill and tap any new holes in the cast iron top as others have suggested. Incra provides several different size bolts. The only real issue I had was the back rail mounts. But it wasn't really an issue when I figured out to just use the bolts that attached the old back rail. It worked beautifully.

Step 4: Rail T-Nuts

Attach the t-nuts to the front and back mounting brackets. Then slide the rails into place. Space the rail dead center of the table. We will adjust this later.

Step 5:

Tighten the t-nut bolts to secure the rail into place. Loosen the bolts on the mounting brackets. Use the positioner arm mounting brackets and clamp them to the bottom of the rails. Move the rail assembly up or down until the backside of the brackets are flush with the top of the cast iron top. This is going to ensure the rails are at the proper height. Then tighten the bolts to secure the rail mounting brackets.

Step 6:

Now it's time to assembly the positioner arm. Assemble the stop knobs and insert them into the right side of the rails. There are 4 stop knobs. 2 on the front and 2 on the back.

Step 7: Installing the Glide Pads

Attach the glide pad to the bottom of the positioner bracket. Install the screw and nuts to each bracket then slide it into play on the positioner cross member. Leave the screws loose as we will need to adjust its position in a later step.

Step 8: Install the Positioner to Cross Member

Flip the cross member over and install the Positioner into place. You will need to space the positioner 11" from the edge. I used a large square and a ruler to get the exact spacing. Tighten the outside screws to lock it down

Step 9: Mounting the Cross Member and Positioner

Remove one of the brackets and slide it on top of the stop knob. Mount the cross member and positioner on to the rails. Then slide the opposite bracket and cross member on the backstop knobs. Then slide the cross member into the front mounting bracket.

Step 10: Adjust the Positioner and Rails

Slide the cross member back so that it's spaced 37 1/4" away from the blade. I used the miter slot and measured 32" because I know my miter slot is 5 1/4" away from the blade. This makes it easier to use a tape measure. Once the spacing is correct. Tighten the screws on the mounting brackets to lock it into place. Make sure the rails are positioned far enough to accommodate this position.

Step 11: Installing the Positioner Arm

Attach the fence mounting bracket to the positioner arm. Then slide the arm into the positioner. Note: there is a small lip on the side of the arm that slides into the receive lip on the positioner. Once you have those lips engaged the arm slides freely. This can be a bit tricky.

Step 12: Install the Fence Hold Downs

Install the Fence hold down brackets into the front and back of the fence.

Step 13: Build the Extension Tables

Time to make the new extension wings (My favorite part). I made the wings out of phenolic laminated plywood so they will not have any seasonal movement. You can use whatever you would like. Melamine or MDF would be a good choice as well. Each wing is supported by a pair of cleats. Rip 2 cleats for each size and then cut them to width according to your spacings. The spacings are going to be different according to the size of the Positioner you purchased. Drill holes into each cleat according to the provided instructions in the Incra manual. Attach the clients using washer, bolt, and nut to the rails. Make sure the head of the bolts you use is large enough to fit into the t-track on the rail. Measure the width and length of the openings and rip the plywood accordingly. Place the plywood on top of the cleats and fastening into place with l-brackets to the cleats on the underside.

Step 14: Final Calibration

  • Place a piece of 3/4" plywood scrap into the miter slot and butt the fence up next to it. Adjust the arm and position so that it's square. Tighten down the screws on the positioner to lock it into place.
  • place popsicle sticks (2 stacked on top of each other) under the fence. Space each pair equally down the length of the fence.
  • With the fence mounting bracket screws loose, raise the arm until it's parallel to the rails. Tighten the bolts on the mounting bracket. Test to see if the arm slides easily. If it does not slide easily, it's not parallel to the rails. Keep adjusting the height until it slides easily. This is a crucial step in the process or the fence will not work properly.
  • Slide the fence to 1/32" away from the blade. Set the fence into micro-adjustment mode by raising the red lever on the positioner to the middle position. Rotate the red dial away from you until the fence kisses the blade. Lock the fence into place
  • Detach the magnetic ruler and slide it down the arm until the zero marking is lined up with the line indicator in the positioner window. Hold down one end of the ruler and attach the rest of the ruler into place. Make a couple of test cuts and adjust accordingly.