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A Turn from the Front. Grip the saw directly above the blade when cutting curves. Take it slow, and let the blade do the work. place the good face of your work-piece down. (In the box at right, you can see a another way to prevent tearout with an upcut blade.) Curve-Cutting Blade. When I need to cut tight curves or if I need both faces of a plywood panel to look their best, I switch to a different blade. This blade has 20 teeth per inch and they point straight out. These teeth have a slicing action that leaves both faces clean. CUTTING TECHNIQUES With your saw set up, you're ready to start cutting. But there's more to smooth jig saw cuts than setup. Here are a few techniques that will improve your results. Cutting Speed. As you're cutting with either of these blades, you'll notice they have a natural cutting speed. This is the amount of material the blade will remove with light pressure on the saw. I know it's tempting to push the saw full-speed ahead and get the cut done faster. But, if you relax and let the blade do the cutting, the cut edge will be much smoother. The Grip. The small size of a jig saw makes it seem natural to hold it in one hand and the workpiece with the other. But you'll find the saw is easier to control if you hold it with two hands. You can then secure the work-piece with clamps. By clamping the piece to the workbench close to the cut line, you can prevent it from vibrating and binding on the blade. Turning Corners. Keeping both hands on the saw works great for straight cuts and gentle curves. But when it comes to turning tight corners, I use a different technique. The problem you can run into is that the cut edge ends up beveled, as illustrated in the left drawing above. This comes from pushing the saw forward too hard while trying to turn the corner. Like a car skidding around a corner, this action puts a lot of pressure on the side of the blade (inset drawing). The solution is simple. I take it slow and try not to put much forward pressure on the saw. Instead, you want to guide the blade around the corner. And, it'll feel like the saw is pulling itself along. Overhand Grip. Then, to get the best control for the turn, I hold the saw with only one hand directly over the blade (photo at left). This seems like the opposite of what I said earlier, but in this position, you can better pivot the saw without pushing it to the side. As the saw comes out of the turn, you can go back to a two-handed grip. And when you're finished, you'll see that it doesn't take a new saw to get smooth, square cuts. ^ Smooth Cuts: Stop Tearout A Masking Tape. To help prevent tearout in the top face of the workpiece, you can apply masking tape to the outline. The tape holds the fibers in place and keeps them from splintering. PUSHING TOO HARD ON SAW PIVOT SAW WITH LITTLE FORWARD PRESSURE A Problem. Too much forward force on the jig saw causes the blade to deflect in the cut. A Solution. Slow down and pivot the saw around the blade. Now, the blade stays straight. BLADE REMAINS STRAIGHT |
