Introduction: How to Make a Better Cross Cut Sled
I have quite a few sleds for different operations. The problem is they can be quite large and storing them in my garage shop is becoming a chore. I decided to create a multi-purpose sled for various cross cutting, compound miter cutting, and dado operations.
- One 24" x 48" sheet of plywood - 1/2" thickness
- One 24" x 48" sheet of plywood - 1/4" thickness
- One 24" x 48" sheet of plywood - 3/4" thickness
- 2 hardwood strips that can be milled to 3/4" x 5/16" x 26 inches long
- 1/2" wood screws
- 1" wood screws
- 3/4" brads
Tools used: (note, hand tools can be substituted where applicable)
- Table saw
- Router table
- Drill with 1/4" bit, 1/2" bit, and various counterbore bits
- Spindle sander
- Orbital sander
- Assortment of clamps
Step 1: Use Caution
This instructable involves the use of various power tools. Where ever possible, use all of the safety guards that the manufacturer provided, and understand how to use the tool. In addition always were personal protective equipment. Safety glasses, hearing protection and dust masks are required for many of the steps detailed here
Step 2: Gather Your Materials
Here you see 2 sheets of plywood I got from a big box store. I grabbed "handy panels" which are basically 1/4 sheets of plywood and roughly 24" by 48"
Step 3: Trim and Layout
I want my sled to be 36" long. so I cut 12" off the piece of 1/2" plywood first.
Once that was complete. I set my fence to 18 inches - half the size of my 36" sheet. From there I marked the blade kerf so I could begin creating my layout
Step 4: Layout Established
Here you can see some of my layout lines. There are essentially 2 things I want to lay out before moving forward:
1. The position of the maximum blade kerf. Based on my initial line at the table saw, I measured 3/4" to the right to account for the maximum (usable) width of my dado stack. I have a left tilt arbor. Be sure you know which direction your arbor tilts before making your layout so your kerf is correct.
2. I then measured 1/8" to the left to account for the blade tilted at 45 degrees
3 - From those reference points. I drew markings on each side to allow for my zero clearance inserts to be screwed down yet never come in contact with the blade
I also laid out lines to cut some T-Tracks to allow use of hold down clamps for hands free operation.
Step 5: Drill Your Pilot Holes for the T Tracks
Because off of the layout lines will be covered by the 1/4" plywood in a few steps, I wanted to establish my holes now.
The T-Track starts 3" from the edge with the fence, and 6" from the front of the sled. The hold down clamp uses a 1/4" bolt with a 3/8" head. In order to be able to insert the head from the top of the sled and not the underside, I drilled a 1/2" hole toward the front of the sled, and a 1/4" hole toward the fence so the bolt cannot pull out when slid all the way back
Step 6: Prepare Your 1/4" Plywood
Based on my reference lines, I cut my 14" plywood to size, and cut my sacrificial zero clearance strips
Step 7: Glue the 1/4" Material to Your 1/2" Base
Following the reference lines I drew, I evenly spread a coat of Titebond III wood glue. I chose titebond III because it has a long open time - meaning it takes a while to set up. Since this step requires a lot of fussing around with layout, clamps, and cauls, I didn't want the glue starting to cure too early.
I first lined up my edge pieces to the layout lines. I then inserted one of the sacrificial inserts before applying clamps. NOTE - this was not glued in place.
Once I was satisfied with my alignment, I clamped the edges to my workbench then applied pressure with the help of my cauls, my portable planer, and a fully loaded tool chest.
I let this clamp overnight
Step 8: Route Your T-Tracks
First, drill your holes through the 1/4" sheet you overlaid in the last step. Now set up a router and a straight edge guide. There are 2 router operations required per channel:
Then establish a recess for the bolt head on the bottom of the hold down clamp to ride in. You want to be sure the groove is deep enough to recess the bolt head completely or it will scratch your table saw's top
With your half inch hole as a reference, insert a 1/2" diameter bit into a plunge router. Plunge the bit into the hole and with a long T-Square, draw a line where your edge guide should go. Attach the edge guide
Route the 1/2" groove first as shown in the second picture.
Without removing your edge guide, change to a 1/4" diameter router bit and then route a 1/4" groove all the way through the board. If you don't touch the edge guide and you are careful keeping your routers sub base against the guide, you will have a perfectly centered groove in your 1/2" channel. Do this for all 4
Now is also a good time to sand the top and bottom surfaces. Going forward there will be fences and rails that will get in your way
Step 9: Install Your Runners
I didn't capture the steps to make the runners as I had done so a while back. It is pretty simple. I like to cut 3/4" hardwood strips then run them trough my planer for an exact fit. They should sit about 1/16" shallow of your miter slot, but be very tight on the sides.
There are many ways to attach runners to cross cut sleds. This method works well for me and is pretty foolproof.
1. First. put some small nuts in your miter channel. I alternate sizes so the runner remains even
2. Apply some tape to the edges of your miter slots. No one wants glue on their cast iron
3. Insert your runners and apply some glue. In this case I didn't need a long open time, so I used gorilla white wood glue (not the polyurethane glue) which sets up rather quickly.
Step 10: Attach the Sled to the Runners
To attach the sled to the runners:
1. Set your table saw fence to 18" or whatever measurement you used to draw your reference lines. This is very important or your replaceable insert will not be in the correct position
2. place the sled on top of the runners with one edge against the fence
3. My planer and tool chest came in handy again in this step. Try to keep the weight centralized over the runners as not to warp the sled. It will be slightly off the surface of the table saw
I leave this for 4 to 6 hours. After that I remove the sled from the tale saw, flip it over and drive a few 3/4" brads to the runners.
Step 11: Build the Fence
The fence is similar in construction to the base. A backer with a removable insert. For the backer, I used 3/4" plywood. I wanted my sacrificial insert to be 1/2" thick. Unlike the base of the sled, this insert will take the full height of the blade.
I cut the 3/4" piece and the two 1/2" pieces long so I could trim them to seize after.
The base of the fence needs to be dead flat. Normally a jointer can take care of this, but plywood is REALLY rough on jointer blades. My fence height is 3 1/2 inches. I cut the 3/4" piece oversize to 3 3/4" inches. Cut your 1/2" plywood slightly oversize as well. This will be explained in the next step.
I then use my sled to reference where the insert needs to go. I applied glue and followed the same process that I did for attaching the base. The insert is not glued, just inserted for alignment.I clamped this to my bench so it would remain flat. Make sure on one edge the 1/2 plywood does not overhang the 3/4" plywood
Step 12: Square the Fence
One advantage to plywood is the edges are flat from the factory (most of the time). The reason I cut the 3/4" piece oversize is so I would have a reference surface to square your fence.
Locate the side of the crosscut sled fence where you were careful not to let the 1/2" plywood overhang, and place it against your tablesaw fence. Set your table saw fence distance just enough to trim off any overhanging plywood on the other side, but at least enough so the blade makes contact with the entire length.
You have now created a perfectly square reference edge. Move your table saw fence to the final desired dimensions (in my case, 3 1/2 inches). Place the freshly cut side against the fence and trim the overhang off of the other side.
Once that is done, trim the edges to match your sled - being very careful that the sacrificial insert will line up with the base
Step 13: Create the Front Fence
Some use plywood, I like to use hardwood here. It looks nicer and takes abuse a bit better. I used a 12" piece of Ash I had. I gave it a nice shape and a quick few coats of shellac.
Step 14: Attach the Front Fence
With the sled upside down on the bench, I center the front fence and clamp it in the middle. I then counterbore some holes and secure the rear fence with screws. Alignment here is not at all critical. the rear fence gives the sled rigidity
Step 15: Tune Up the Runners
It's likely the runners will need a little tweaking to slide smoothly. You want a very firm fit with no side-to-side play, but smooth back and forth motions.
Now the front fence is on, slide the sled back and forth on the table saw. If it is tight (and it will be), sand the edges of the runner. I secure a 1/2 sheet of 120 grit sandpaper to a flat hardwood block. Take long and even strokes on each side of the rail; checking progress frequently until your are happy with the results. Be careful not to sand too much off. Side to side play will reduce the accuracy of the sled.
Step 16: Cut the Kerf
Once your sled slides well, cut a kerf line from the front of the sled to right about where the back fence will be. Do not install the sacrificial insert yet
Step 17: Install the Rear Fence
Alignment of the rear fence is the most critical part of this project. Before this step, I drilled counterbored holes in the bottom of the sled and started the two outermost screws
With the kerf cut, I insert a rule from a combination square that is the same thickness as the kerf. With a known good speed square, I carefully adjust the fence until it is square on both sides, then drive the screws in. After the outermost screws are set, I verify the alignment. If it is still good, I will drive in the rest. Be aware of the blade kerf on your full width dado cuts when inserting screws.
With the fence attached, I further verify the alignment using the 5 cut method and make adjustments as necessary
Once this is complete I give the entire bottom of the sled a coating of furniture paste wax
Step 18: Set Up Your Sacrificial Insert
I attached both the bottom insert and the fence insert with countersunk holes. They both should slide in easily. If not, use your sandpaper block to adjust the fit.
After drilling the holes, I inserted the screws by hand. Power tools can set the screws too deeply and pull the insert down. You won't have that critical flat surface.
- Tip -
Remove both inserts and keep them for templates. Mark the front and back. Drill holes in another set of inserts and install them. Once you cut a kerf, it will cut the insert in half. This makes it difficult to use it as a template in the future
Once you have your Inserts installed, cut your kerf
Step 19: Make Some More!
I then created one for a 1/2" dado cut and a 45 degree miter cut, as well as different inserts for different blades I use. Having an insert specific to a blade ensures a zero clearance and a cut that is as clean as possible
Step 20: Add Accessories
I added a handle and a box to the back. Sometimes the blade goes past the fence. This gives me another 4" and a reminder of where not to put my hands.
You can also see the hold down clamp that rides in the T-tracks I cut. Now there is no reason to put my hands near the blade.
On top of the fence is an Incra T-track plus with a rule and a T-track stop. This makes precision repeatable cuts easy.
I also added my miter bar from my other sled. Using the T-Tracks in the sled, this can be set to a multitude of different angles for miter cuts and compound miter cuts. I also installed a T track on top of it for a stop block.
I am replacing 3 sleds with this one, and I now have the precision and flexibility of a zero clearance for any cross cut I can make.
If you have any questions or need anymore info, feel free to send me a message.