Any true shop rat knows that the best tool for making perfectly square crosscuts isn’t a miter saw—it’s a table saw. That’s why table saws come with a miter gauge. But the truth is, if you want to make perfectly square cuts, you’re better off leaving the miter gauge in the rack and building a crosscut sled.
A table saw equipped with a crosscut sled is more accurate and allows you to crosscut material up to 2 ft. wide depending on the size of your saw’s table. This sled design is the world’s easiest and fastest to build. It’s made with scraps you probably have lying around the shop and three pennies you’ll find under your sofa cushions.
You’ll need a 2 x 2-ft. scrap of 3/4-in. plywood; any type, as long as it’s flat. Dig up a 2-ft.-long chunk of super-straight hardwood 1x3. That’s it for the wood, but you’ll need double-faced tape and 3/4-in. No. 8 flathead screws as well. It’s best to have two adjacent factory edges on the plywood so you know you’re working with a square corner (see Photo 2). Remove the guard and unplug the saw to build the sled. (To find out how to build a larger, two-runner table saw sled, type “table saw sled” in the search box above.)
Most miter gauge slots on full-size saws are 3/4 in. wide and 3/8 in. deep. Rip a 5/16-in.-thick, 24-in.-long strip off the 1x3 and test the fit in the slot. The strip should slide smoothly with very little play and be slightly below the surface of the saw table. If the strip’s too wide, you’ll have to hand-sand the edge a bit until you get it to glide smoothly. If you have a surface planer, use that to get perfect dimensions. It’s worth spending time on the strip since it’s the key to smooth, accurate cuts with the sled. Some saws have slots of different dimensions, and you’ll have to custom-make a runner that fits.
Tip: To find wide spots in the runner, rub the slot sides with a pencil. Slide the sled through a few times and the graphite will show you where to file or sand more.
Apply double-faced tape to the runner (Photo 1). Keeping one end of the runner even with the saw table edge, set the fence to 23 in. and lower the plywood onto the runner. Keep the plywood tight against the fence and even with the edge of the table as you lower it into place (Photo 2). Flip the plywood over and then drill four evenly spaced 1/8-in. countersunk pilot holes. Add the screws but don’t overtighten them (Photo 3). That would make the runner bulge at the screws and cause binding. Move aside the fence and give the sled a test slide. If the action is a little tight or sticky, hand-sand the runner edges until the action is smooth.
Rip the leftover hardwood down to 2 in. for the sled’s fence. Glue and nail the fence to the plywood with 1-1/4-in. brads (Photo 4). If your saw table has a sharp corner at the infeed edge, prop the fence up with the pennies before fastening so it won’t catch during sled operation. Run the sled through the blade to true up the outside edge and cut off the excess fence. You’re now ready to make perfect crosscuts. But never use the fence while you’re using the sled. That’s dangerous because even with a sled, a workpiece can get pinched between the blade and the fence and kick back at you.
Original article and pictures take http://www.familyhandyman.com/DIY-Projects/Woodworking/Woodworking-Tools/how-to-build-the-three-penny-crosscut-sled/View-All site