Jigsaw Sort-Out

I originally understood that a jigsaw was a hand-held cutting tool, but my early experiences with one particular machine left me thinking I was actually holding a small arc welder. The tool was an economy model, and not up to the task of cutting the 1-inch thick oak I was working with. Blue sparks and a mushroom cloud of acrid smoke marked the tool’s last gasp during that job. The experience didn’t quite set my clothes on fire, but it did kindle a renewed conviction that the only power tools worth owning are good ones. And choosing well often means paying more than bargain-basement prices. The first thing you need to understand before you buy is that jigsaw quality varies enormously across the board. There are some wonderful machines out there and some absolutely terrible ones. Be warned. Most of the junk is marketed directly at you as a do-it-yourselfer.
Jigsaws are safe, relatively quite power saws that cut wood, plastic and metal with an oscillating blade. They're ideal for light home renovations, crafts and curved woodworking cuts. And if you and I were walking the aisles of a big box hardware store looking to choose your first jigsaw, I'd start by sharing philosophy. I believe that buying one good power tool in your lifetime is cheaper and more efficient than buying three or four bad ones. And in the spirit of this quality quest, the first thing to look for in a jigsaw is orbital blade action. This is an adjustable feature that allows the blade of a saw to move in a D-shaped pattern during each cutting stroke, instead of just straight up and down. The result is a much faster cutting action in wood and plastic than you’d get with straight line blade movement. In fact, you’ll work through material about three times faster with orbital action than you will without it, all else being equal. The trade-off (and there always is one) is that a D-shaped blade pattern also yields a rougher cut. That’s why all orbital jigsaws can be adjusted to offer no orbit at all (smooth but slow cutting), all the way up to maximum orbit for fast action through rough materials where smoothness doesn’t count. At its maximum orbital setting, the D-shaped blade pattern is extreme enough that you can see it. The blade moves straight down along the back of the D, then curves outwards as it moves up along the front of the D. 
Variable speed is another useful jigsaw feature because it widens tool versatility. While it’s handy to be able to slow down blade action when slugging through thick hardwood, it’s absolutely essential to pull back on speed when slicing through plastics and metal. A single speed machine offers less potential because it can’t tackle the full range of materials that a variable speed jigsaw can.
Besides speed adjustment capabilities, jigsaws also divide into two groups based on how you hold them. Barrel grip saws have no actual handle, but rather a small diameter body that you grip with your dominant hand, and a mushroom knob above the blade for the other hand. Top-grip saws have a larger body with a handle that arcs above it. Good jigsaws are offered in both formats, though I prefer the barrel grip. Hold both when you've in the store before you buy.
Any jigsaw is only as good as its blade, and the saw you choose affects the choice of blades available off the shelf. The most popular of these is the so-called “Bosch-style”, named after the company that made it popular. You’ll find that the best blades most often only come with this style of anchoring flange. Good jigsaw blades aren’t cheap, either. Expect to pay a couple of dollars or more each, but their performance is worth it.
Even a good jigsaw can’t do everything. One limitation is power. Even a heavy-duty machine has to work hard to cut through 2-inch thick wood, especially parallel to the grain where the going gets tough. That's where you'll need to use a coarse blade. Another limitation is accuracy. Since the blades of all jigsaws are only supported on their top ends, the bottom end is free to wander a little from side-to-side during a cut. This can be minimized by using a sharp blade with the correct tooth spacing, but the tendency for blade wander never completely disappears. That’s why you can’t count on jigsaws to create a cut with an absolutely square edge. For that you need a hand-held circular saw or tablesaw.
Good tools are like friends. The more success you have together, the more you like them. I bought my jigsaw more than 15 years ago and it's seen me through many professional and DIY jobs. I also lend it out to friends who always say what a joy it was to use. That's what a good tool can do.
Sidebar: Jigsaw Buying Basics
When assessing jigsaws in the store look for:
*orbital blade action to speed cuts through rough material
*a motor that draws between 4 and 5 amps according to the name plate
*variable speed capabilities that allow blade movement to be reduced to a frequency of one or two cycles per second
*a couple of dozen different kinds of blades that fit the machine.
*a carrying case that holds blades, wrenches, instruction manual and goodies.