13 pointers for perfect plywood cuts
You don't have to settle for rough, splintered edges when cutting plywood. Nor do you have to wrestle large, awkward pieces while placing your back at risk. Just use these simple tricks to get great results.
Crank it up for quality
When cutting plywood on the tablesaw, raising the blade height can make a big difference in cut quality. Most of the time, safety dictates setting the blade low, but this cuts away the underlying plies first, leaving the top face unsupported as the teeth slice through. For a cleaner cut, raise the blade a couple of inches, as shown. The teeth contact the sheet while moving almost straight down, so the face veneer is supported by the plies below.
Zero in on the best table insert
Before cutting plywood, swap your tablesaw insert plate for a zero-clearance model, as shown in the photo, to dramatically reduce chip-out on the underside of the sheet. The blade cuts the opening in this type of insert to match its thickness, offering support to the workpiece edges along the cutline. You can buy zero-clearance inserts for most saws.
Score early, score often
If both faces of the plywood will be visible on your project, you need to minimize chip-out on each side. Do this by making a scoring pass first, with the blade raised only about 1⁄16 " to 1⁄8 ", as shown. Then raise the blade, as advised in tip 1, and make another pass to cut completely through the workpiece.
Take smaller bites
The blade you choose makes a difference in the quality of your cuts. The photo shows a few options.
On the tablesaw, a combination blade, because of its split-personality design, cuts smoothly if you keep it sharp and use a slow feed rate. To get the best-quality cuts, invest in an 80-tooth blade designed for sheet goods. The small teeth take little bites to reduce chip-out and are steeply beveled at their edges to score the veneer face. You'll have to slow your feed rate, but will get a much smoother edge.
Most handheld circular saws come equipped with a blade best suited for making rough cuts in construction lumber. Ditch it fast, and then invest in a carbide-tipped plywood blade, or use disposable thin-kerf steel blades that sell for just a few dollars.
Take a sure rout to clean edges
So you've tried everything, and just can't get a clean cut. What do you do now? One remedy: Cut your plywood from 1⁄16 " to 1⁄8 " oversize, and then trim it to final size, as shown, by running a bearing-guided pattern bit along a straightedge.
Believe the tale of the tape
Even if you squelch major chip-out, you may still get minor tear-out of small fibers. Combat this by covering the cutline with masking tape, as demonstrated in photo. The blue, low-adhesion variety works best because it holds the fibers in place, but peels away easily without grabbing splinters. Be sure to press the tape down firmly.
Get some support
Cutting plywood sheets on your tablesaw is possible if you support the sheet well throughout the cut. As the photo proves, you don't need fancy equipment or a huge saw table, either. A roller (or a sawhorse outfitted with a proper-height support) placed in line with the planned saw kerf holds the end of the sheet steady at outfeed. To support the side of the sheet, be creative by positioning your drill-press table, as we did, or maybe clamping a piece of scrap stock to your jointer to match the saw table's height.
Stay on the fence
Even with your sheet well supported on a saw table, you have to concentrate on keeping it firmly against the fence as you cut for best results. Push from one side of the blade, as shown in the photo. Your hand nearer the blade pushes straight forward. With your hand that's farther from the blade, push harder, and toward the cutline at the outfeed end of the sheet. As you near the end of the cut, reposition your hands to straddle the cutline so you can push the cutoff pieces through.
Base success on hardboard
If your circular-saw blade causes tear-out, try the method shown: Cut a piece of 1⁄4 " hardboard to match the size of the shoe. Retract the blade, lift the guard out of the way, and attach the hardboard using double-faced tape. Start the saw, then slowly lower the blade to create a zero-clearance blade opening. Cut with a slow feed rate and use extra caution because of the exposed saw blade.
Joint from both ends
To trim small plywood pieces from rough to final size, try running them across the jointer, as shown. But don't just throw the sheet on and run it through -- you may get chip-out at the trailing corner. Instead, place one face against the fence, and joint 2" or 3" along the edge you wish to trim. Then place the opposite face against the fence, and joint the remainder of the edge.
Face up to facts
If you're cutting plywood on a tablesaw, the blade's teeth enter the wood from the top and exit the face that's against the table. This is where chip-out will most likely appear. So, keep the good face up on the tablesaw, as shown in the photo.
When you're cutting with a handheld circular saw, on the other hand, remember that the blade's teeth enter the workpiece from underneath, and exit at the top. It's where the teeth exit that you'll have chip-out and splintering. For this reason, place the good face down to get a clean cut.
Get down with it
A sheet of 3⁄4 " hardwood plywood can weigh 60 or 70 pounds, making it difficult to move around. If wrestling a sheet that heavy onto the tablesaw sounds daunting, rough-cut it into manageable hunks first, using a circular saw. Just lay a 4x8' sheet of 2" foam insulation board on the floor, and place your plywood on top of that, as shown.
Seek simple guidance
Many of us are a little straight-line challenged when using a handheld circular saw. Sure, expensive store-bought guides are available, or you can make a shop-built straightedge guide if you cut lots of sheets. But a simpler solution exists as close as your scrap bin. Make a guide using the factory edge of a 10"- to 12"-wide scrap of plywood or hardboard. Clamp it in place for your saw's shoe to ride against, shown in photo. If you're cutting on foam, simply chop out notches to create clearance for the clamp heads.