Adjustable Crosscut Sled
Shop Jig: Make accurate and dependable 90° cuts with this adjustable table saw sled.
I recently upgraded my table saw, which meant I had to construct a new crosscut sled. My previous sled had been a source of frustration, so I resolved to make a new one with a few improvements. You may find some of these ideas useful when building your own sled.
My research involved a thorough search on the Internet where I checked out many sleds and looked at different options. Still not satisfied, I finally decided to design my own sled. I wanted something very simple, without mitre attachments, tenon cutting attachments, etc. I needed an accurate sled that would provide dead-on 90° cuts.
There were two distinct problems with sleds I had built previously and I wanted to address these concerns when designing the new sled. The first problem was the runners. I chose to use Ultra High Molecular Weight (UHMW) runners on the new sled rather than wooden ones because they glide easily in the mitre slot and will not change with humidity. The real improvement, though, is the adjustable fence that you can check for square before every job. Zero-clearance inserts were also a must and the stop is a simple one using a ‘BlackJack’ universal fence clamp.
Build it up
Glue together a couple of layers of Baltic birch to achieve an acceptable thickness for the fences.
Use pennies to raise the UHMW strips in the mitre slot and attach two-sided tape to ensure the strips are in the right location.
Using replaceable 1/4" MDF strips in the kerf area allows you to always have zero-clearance support to back your cuts.
The blade guard box will cover the blade as you get to the end of your cross cut, keeping the blade safely tucked away.
Stop wasting time
Adding an adjustable stop will save time by allowing you to make multiple cuts without measuring every cut.
When constructing the fence, it’s a good idea to cut the fence and front stabilizer parts a bit oversized, and then trim them to final dimensions when cured. Glue the parts together to form one 1-3/8″ thick piece. After the glue has cured, be sure to scrape off the excess before trimming.
For my sled I chose to build two fences: one at 28″ for everyday use as documented here and one at 48″ for longer boards. Cut the rear stabilizer to size and the parts for the blade guard assembly. I found that a 3/16″ dado at the bottom edge of the fence serves well as a sawdust groove to avoid buildup.
Begin laying out the cut lines on the fence, the front stabilizer and the rear stabilizer as indicated. Cut away the waste material on the band saw leaving the line and then sand each part to the line to remove the blade marks. Finish by breaking all sharp edges with 120-grit paper.
Using a 3/4″ collar, 1/2″ straight bit and plywood template, route the recess in the face of the fence for the 4 x 3 x 1/4″ MDF zero clearance insert and square up the corners with a sharp chisel. Alternatively, the material may be removed with a Forstner bit on the drill press.
Cut the deck to the size indicated. You may choose to make your deck larger, but I found that 24 x 30″ seems to be ideal for moving the sled on and off the saw. Prepare the UHMW runners by drilling 9/64″ shank holes approximately every six inches and counter sink for #6 screws. Line the table saw mitre gauge slots with pennies so that the runners sit proud of the surface. Insert the runners and shim with business cards or paper so that they are snug and apply carpet tape in between the screw holes. Seat the deck on the runners, ensuring that its center line is in line with the blade. Carefully remove the deck so that the runners come away with it and drive the #6 x 1″ screws but do not seat them. Finish with a screwdriver to avoid distorting the runners. You may have to fine tune the runners with a cabinet scraper if they are too tight. The goal is to have the runners running free but not sloppy.
Next, cut a 4″ wide by 1/4″ deep dado at the center of the deck to receive a 1/4″ MDF zero-clearance insert. With the same setup cut a 1/4″ x 3/4″ rabbet in the blade guard sides. The handle is fashioned by drilling two 1-3/8″ holes as indicated. Remove the waste in between the holes with your jigsaw and finish by rounding the edges over with a 1/4″ round over bit and sanding smooth.
Assembly of the sled begins by fastening the front stabilizer to the deck with six #8 x 1-1/2″ screws. Insert the zero-clearance insert in the fence and secure with four #6 x 1/2″ screws counter-sunk on either side of the cut line. Insert the zero-clearance insert for the deck and secure with ten #6 x 1/2″ counter-sunk screws. When making additional inserts use these originals to locate the screw holes.
Mark the carriage bolt locations on the underside of the sled as indicated. Drill recesses 1/4″ deep for the carriage bolt heads using a 3/4″ Forstner bit and 1/4″ through holes in the centre of each recess. On the drill press drill the 1/4″ pivot through hole in the fence as indicated and then drill the three through holes in line to make the right adjustable slot and then clean up the slot with a chisel. Insert the carriage bolts, install the fence on the two bolts, add washers and wing knobs and then tighten to seat the bolts.
Glue and assemble the blade guard box with four #8 x 3/4″ screws. After about 30 minutes remove the screws and round over edges along the top and back, re-insert the screws and attach to the rear stabilizer, with six #8 x 1-1/2″ screws. Install the acrylic cover with five #6 x 1/2″ screws. Finish by fastening the rear stabilizer assembly to the deck with four #8 x 1-1/2″ screws.
Cut a stop block and drill to fit the BlackJack Universal Fence Clamp.
Using the Sled
Set up the sled by running it through the saw until the blade reaches the fence. Turn the saw off, and then crank the blade up as high as it will go. Loosen the right adjustable wing knob and use a square to adjust the fence square to the blade. Be sure to set the square against the blade and not the carbide teeth and then tighten both knobs securely. A good test is to cut a waste board. If the fence is not square it will be revealed by a gap when you flip one piece over and put them together on your saw top.
Prior to every job, I check the fence. A re-adjust is rare but you may at times bump it out of position when moving it around. With additional zero clearance inserts this sled would also be ideal for cutting Dados. I didn’t apply a finish to the sled but you may elect to do so. You may also decide to wax the bottom of the sled, but I find this isn’t necessary if I keep the saw top waxed. Your adjustable crosscut sled is now ready to go to work.