By Ande Waggener
Although a circular saw won’t fit in a well-assembled toolbox, it’s still an essential tool if you do a lot of DIY projects. A tool, however, especially a dangerous one like a circular saw, can only perform as well as you do. In other words, you need to know the circular saw basics for staying safe and getting the best out of your circular saw. Here are four tips for the proper operation of a circular saw.
Note: All circular saw operation requires that you follow proper safety precautions. Always wear eye and ear protection, and always keep your hands (and all other body parts) away from the blade.
1. Properly Set Blade Depth
Some people think circular saw cutting depth is a matter of personal choice as long as you at least set the saw deep enough to get through the wood you’re cutting. This isn’t true. Getting the blade depth just right is important for two reasons.
First, because circular saw safety is challenging enough when the saw is used correctly, you don’t want to make the saw even more dangerous than is necessary. When you have too much blade exposed because your blade depth is over-deep, you create a far greater likelihood of severe injury.
Second, when its blade is set too deep, a circular saw can bind and kick back. This is a safety issue as well, but it also prevents the blades from cutting efficiently.
The proper cutting depth for a circular saw is a quarter-inch to a half-inch below the board you’re cutting. To set your saw at this depth, retract the blade guard and hold the saw against the board you’re going to cut.
Loosen the saw’s depth-adjusting knob or lever and move it until the blade extends a quarter-inch to a half-inch beneath the bottom of the board. Tighten the knob or lever.
2. Let the Cutoff Piece Fall
When you’re first learning to use a circular saw, it’s tempting to hold the piece you’re cutting off so it won’t fall to the ground. But don’t do this. This binds the wood so that the saw doesn’t cut smoothly and efficiently. Always let your “cutoff” (the piece you’re cutting off) fall freely after it’s cut.
But, you’re thinking, won’t this damage a good piece of wood intended for a nice project? Well, yes it will. Not only can the falling piece snap off and possibly leave a bit of a broken splinter in the process, but it could also be damaged when it hits the ground. You only want to let a cut piece fall to the floor if you’re working with framing lumber. For nicer wood projects, here’s what you do:
Set up your cutting area so the board you’re cutting is supported on both sides of the cut. To do this, elevate the board you’re cutting by placing it on two-by-twos or two-by-fours spaced no more than about a foot apart.
This provides the support you need so that when the cutoff falls, it’s not going to snap off because it won’t be falling more than a couple inches.
Even though you want the board you’re cutting to be supported, never cut a long piece of wood that’s supported on both ends across a couple of sawhorses or other taller supports. When you do this, the board will bow downwards as the cut is nearly complete. This pinches the blade inside the cut, which will make the saw or the board buck. Not only is this a safety hazard, it usually damages the board you’re cutting too.
3. Start Over if a Cut is Going Crooked
Cutting wood in a straight line isn’t a skill you’ll have right off the bat. It takes a bit of practice. The hardest part is getting off to a straight start.
If you begin cutting and you can see that you’re off to a wonky start, don’t try to correct as you cut. It’s quite difficult to get a saw back in line as you’re using it.
So stop. Wait until the blade stops spinning. Remove the saw from the cut you started.
Line up with the cutting mark again and start over.
Keep practicing, and it won’t be long before you’re cutting straight without any difficulty.
If, however, you want to get a straight cut right from the beginning, invest in a carpenter’s metal straightedge. Then all you need to do is clamp the straightedge to the board and the base you’re sawing on (either sawhorses or plywood set up on sawhorses).
Then you run the saw guide along the edge of the metal straightedge as you cut.
Be aware that when you do this, your cut line will end up a distance from the straightedge. That distance is the distance between the guide edge of the saw and the blade itself, so measure this distance and account for it when you place your straightedge on the board.
This saw, for example, has 1-and-3/8-inch space between the left side of the saw blade and the right side of the saw guide. So what you’ll do is mark the spot you’re going to cut, then measure 1-and-3/8-inches (or whatever measurement you got from your saw) from there, and that’s where you place your straightedge.
4. Secure Long Boards for Rip Cuts
If you’re going to be “ripping lumber,” which means to make cuts along the full length of a long piece of lumber, a circular saw is not the ideal tool for the job. “Rip cuts” are best done on a table saw because these cuts require more support. Most DIYers, however, don’t have table saws. If you don’t, you can still use a circular saw to make a rip cut. To make a straight rip cut with a circular saw, however, you’ll need to secure the board.
To do this, clamp the board on both sides to your sawhorses or your base plywood on the sawhorses. If the board you’re going to rip is narrow enough that you can run the guide edge of your saw along one edge of the board as you cut, you only have to clamp one side of the board to your sawhorses because the pressure of the saw along the edge will balance with the clamps to keep the board in place
Becoming safely proficient with a circular saw takes some time, but it’s time well spent. When you know how to handle a circular saw, it will open up a vast range of fun DIY projects for you to do. Here’s to happy and safe cutting!
Images used with permission, courtesy of Ande Waggener