The circular saw is the most dangerous, misused, abused tool in the construction business.
When they made the first portable, electric circular saw they put the motor on the right, the blade on the left and the handle was above the blade. When you made a cut and got to the end, the weight of the then big and heavy motor would naturally make the saw fall off to the right and butcher the end of the cut. So, an individual came up with the bright idea of putting the motor on the left and the blade on the right, which left the main weight of the saw and the majority of the base on the stable member of the cut. They didn’t realize that with the blade on the right, a right-handed person had to lean over the top of the saw to see the line of the cut.
A few years ago Porter-Cable came out with the 345 saw boss and the 423 Mag, blade on the left, and moved the handle where it has equal gravity pull when you hold the saw and make a cut. Craftsman also has a five-and-one-half-inch saw like this. Now some other manufacturers are seeing the light. Before this, all right-handed people had were worm drives with the blade on the left.
If you use your right hand to run a saw, buy one with blade on the left; if you use your left hand, buy one with the blade on the right. It is very dangerous to be leaning or out of position when making a cut and you need to see the line to
make an accurate cut. The position of making a cut with an electric saw is the same as making a cut with a handsaw or hacksaw. The cut line, the blade, your forearm, elbow and shoulder should all be in one straight line.
First and foremost, when you go to cut a board make a mark for the cut. You need to check your tape and make sure the hook is not bent. Buying a good tape is an investment in your job, not a cost.
Measuring and cutting lumber to length is the most important thing you will do when building a structure if you want the building, structure or cabinet to be plumb and square.
The mark on the left in this photo is the way about 90 percent of the carpenters I know mark a board. Then they make a mark with a SPEED® Square on some part of it and then cut on the left of the line sometimes and sometimes on the right of the line. Who knows?
The small straight mark on the right is the exact place you want the blade to cut and is the correct way to mark a board; the wing mark on the left of the small mark is the waste side, and wing is waste.
Always let this procedure remind you of loading a gun. Keep your finger off of the trigger (switch) until you are ready to make a cut. It’s the same principle as keeping your finger off the trigger of a gun until you are ready to make a shot. When you plug a saw into a power cord you have created a power supply for a tool that could easily kill you or maim you for life. If you plug a tool cord in backwards (and it can be done) you have created reverse polarity, and it can kill you. Ask any electrician.
Do as this picture shows; get some Wite-Out and paint the wide prong side white
(wide-white). This is the white (neutral) wire in the cord. Then you won’t have to look each time and try to figure out which way the prongs go in.
This little suggested procedure could one day save you or someone else’s life.
Always have a good crowned table to cut on. Never cut a board in the middle that is just lying on two saw horses, it will sag or collapse about two-thirds of the way through the cut and bind the saw and cause the saw to kickback at you. The only time you can safely cut a board using only two sawhorses and no frame table is when you are only cutting an end off.
Never use a circular saw to notch or cut out a stud that is in a framed wall. The saw will buck and you could end up with a 4000 RPM saw blade in your chest. Use a reciprocating saw for this procedure.
I show how to build a crowned frame table to mount on saw horses to cut lumber on and use as a work table on my Web site, but if you don’t have one, use a couple of 2x12s on the sawhorses to cut on. A frame table will pay for itself
over and over, in time and labor. Just make sure they don’t bow down. When you cut a board and it is bowed down, your saw will bind and kick back, which is very dangerous.
Always have a place to put your saw. Never set it down on the blade guard, never drop it on the ground and always lay a saw on its blade side with the side
the blade is on.
Two other procedures I discuss on my site are to install a hanger and frame hook on your saw. These two small additions should be on every saw that is sold. A lot of saw injuries are caused by the person using the saw standing on the cord. When you are cutting and then you run out of cord the saw could kick back and cut you.
Keep all of the area around where you are using a saw clean, and leave nothing that could cause you to trip and fall while carrying or using a circular saw.
Furthermore, keep the whole jobsite clean. I have been to jobsites where
there would be piles of cut off lumber, and the carpenters would have to walk over these piles (tripping and falling) to make a cut or to get material. This makes no sense. Besides that, if you keep your scrap stocked, you can use it, instead of cutting a new stud for a 24-inch block. There were over 250,000 saw injuries in 2007 that required emergency room care.
Now we are ready to make a cut. First, set the blade depth of the saw blade the thickness of the board to be cut plus one-eighth of an inch. Fill your saw cuts on your frame table with drywall mud when you get a lot of them in your table. This will keep a smooth clean surface to saw.
I marked on the back of my saws the depth of cut the plus one-eighth of an inch. One and one-half of an inch is actually one and five-eights inch depth of cut. This saw is set for a quarter-inch cut, but the actual blade depth is three-eighth of an inch.
Make sure the blade is set at 90 degrees to the base for a square cut. Place the
nose (front) of saw base on the board to be cut with the blade about one-quarter of an inch from the board to be cut, align the blade with the mark as straight as you can, slide your SPEED®
Square up to the side of the base and grasp it with your hand and secure it to the board. The side of the saw base and the SPEED® Square should be exactly parallel.
Start the motor and slowly push the saw forward until it just touches the board. If you are a little off the mark, back the saw up one-eighth of an inch (while it is still running) and the vibration of the saw will let you go to the left or right and get the blade lined up with the mark.
Now you can go ahead and push the saw slowly through the board and let the saw do its job. Do not crowd the saw (push it too fast). You will feel when the saw has cut through the board because they will both move slightly but enough so you will see and feel them separate.
Now, do not move the saw. Let the motor and blade come to a complete stop. Never lift or move a saw from a cut or take it off the member while it is still running. Always let a blade stop before removing from the completed cutting position. If you will do this on every cut you make, the rest of your life, your chances of getting cut with a circular saw are almost zero. Why would anyone not use this procedure?
Go to any job, anywhere, and see how many people let their saw stop running before they lift it out of the cut. I can already tell you what you will see—hardly any.
After a few hundred cuts, you will learn to let go of the switch before the cut is complete, and the saw will be dead when the saw makes the completed cut.
Now for those of you that have used a circular saw very little and that I have instilled a fear of even picking a circular saw up let me tell you that a saw is a safe tool if used properly.
Proper, safe procedures of using a circular saw are easier to learn than improper procedures. You could not pay most of the carpenters I know enough money to read and use the information in this article. They know it all. They
are the ones you want to stay away from when they make a cut.
For your first few hundred cuts, I suggest not using a SPEED® Square as a guide. Make your mark, then draw a line on the board and make the cut. It takes a little longer, but it will build your confidence, using a saw. Never depend on a
blade guard to protect you from getting cut. Blade guards are a piece of machinery and they are notorious for hanging up and not going back down, especially when you drop the saw on the guard a few times. The question is not if a blade guard is going to hang up; it is when. Keep the guard lubricated and keep the housing clean of pitch and sawdust.
On a new saw or old saw, check all of the screws and bolts and make sure they are tight. About 75 percent of carpenters keep their guards tied up. Some carpenters know how to use a saw, but a lot of them don’t.
Never cut a board backwards, as the picture shows. When you cut about three-
fourths of the way through the board the saw will bind and kick back. This is very dangerous. You are not in control in this position, all you have to do is get on the other side and make the cut and let the small piece fall to the ground.
One more thing: If you are cutting a board and the motor slows down, you are either crowding the saw (pushing too hard), cutting on a bowed down table, have a dull blade or you are into pitch tension. Pitch tension, when cut into,
will close or open the saw cut you have made. I have cut into some 2x12s and the saw would bind in the first 6 inches of the cut. I would get the saw out and the saw kerf that I cut would be closed. I was ripping a 1x12x8 one day and ripped it about 4 inches and looked at it and it opened up nearly 2 feet at the end where I started, pitch tension.
This is usually in heart sawn wood (center of the tree). Pitch tension is created by kiln drying the wood to fast. If you are cutting a crowned board, start your cut on the crowned side. The pitch has activated on the crowned side, and the kerf will open as you cut. The pitch will close your kerf on the sagged side.
If your saw slows down and goes to binding, stop the motor and pry the blade out of the cut. Try to cut it from the other side or throw the board away.
injuries” on the Internet and look at the pictures. They are horrifying. I have asked many major carpentry associations to print this saw procedure. If they would and all people using saws would follow these circular saw procedures, exactly, to the letter, injuries using a circular saw would almost come to a halt.
Take it slow and easy when you start using a circular saw; follow these instructions down to the last letter.
About the Author
Visit his Web site for procedures for using a miter saw and a table saw. The author welcomes questions about using a saw and can be reached at firstname.lastname@example.org.
Credit: Renovate with Tommy Mac