Before I could finish the Christmas presents I’m working on I needed this jig for my tablesaw.
Cross cut Sled
The first jig I needed was a cross cut sled. A cross cut sled lets you cut 90 degree cuts on a table saw when cutting across long narrow pieces of wood. The crosscut sled rides in the slots on a tablesaw.
Before starting this project I made sure that my saw blade was square with the table. If your blade isn’t square with the table, making a sled is kind of pointless.
I started by picking up a 3/4 inch square dowel. I believe it is poplar. This will go in the 3/4 inch tablesaw to guide. Since the slot is 3/4 exactly and the dowel was 3/4 too it didn’t slide very well. I used the hand plane to make it just slightly smaller so it would slide smoothly.
I then cut the dowl into three pieces lengthwise so that the two outer pieces don’t quire reach the bottom of the tracks. The middle piece was scrap. The two remaining pieces don’t quite touch the bottom of the tracks. This is so that the sled itself is what slides across the table, the dowels are just there to guide it.
I used a couple of nuts to raise the dowels above the level of the table and laid down a bead of glue.
I then placed the sled on top of the runners. The sled itself doesn’t need to be oriented exactly correct since the runners are in the tracks already.
I let it dry like this for about 30 minutes before bringing it inside to finish drying.
While it was drying I used the tablesaw fence to cut flat edges on two pieces of 2×4. The cross cut sled is going to get cut in half, so these will be glued on vertically and the sawblade won’t cut them completely in half.
The front 2×4 doesn’t need to be square with the blade. It’s just there to hold the two sides of the sled together.
I glued the front 2×4 in place and let it dry. I then ran the sled most of the way through the saw blade. I left about an inch uncut on the back side because the 2×4 isn’t in place yet.
The back 2×4 needs to be square with the blade. When we make cuts with the sled, the material will butt up against the back 2×4, and being square will ensure that our cross cuts are 90 degrees square with the flat side of the material.
To square it up I temporarily put in a single small nail in one corner of the back fence so the fence can move. around.
I put down a layer of glue under the back 2×4 and spread it back and forth a bit. With the one fixed point I used a square and the cut I made previously to get the correct angle for the back 2×4, then clamped the 2×4 down to dry. Finally, remove that temporary nail so it doesn’t scrape the tablesaw table.
And that’s it! Simple and cheap.
The first time I use it the blade will cut through the back 2×4 and through the rest of the plywood. I had to make one more jig to continue working on these Christmas presents, but I’ll save that for a new blog post tomorrow.