Significance

• The blade on a circular saw draws its cutting power from the high rate of speed at which it rotates. The blade is protected by a metal sheath, which surrounds the blade and retracts as the power is turned on and the saw comes into contact with the piece of wood. When the cut is complete, the metal cover quickly slides back into its place surrounding the metal sheath.
  
  Circular saws also come with many different types of blades designed to be used in various situations. The most common blade used is a carbide-tipped, general-purpose blade. Other common blades include a fine-toothed cross-cut blade, a ripping blade, a dado blade and planing blade. All of these blades have their own special task.
  
  

Warning

• When working with a circular saw, the most important thing to remember are safe operating procedures. The first area of concern is your work space. Make sure you always have a set of sawhorses to support your lumber and also be certain you have a direct line to the nearest power source that is dry and safe. Water and electricity do not mix, so you need to take extra precautions especially if working outside.
  
  Next, inspect your extension cord to certify that there are no exposed wires or kinks in the line. Another thing to check is the conductivity of the cord. Electrical tools draw a lot of current and circular saws are close to the top of that list, so use a cord that is rated for high amperage.
  
  

Function

• Once your power source is secure, make sure your work space is laid out so that you have room to work. All materials should be neatly stacked nearby, and the sawhorses should be clear except with the board you are cutting. Cross-cutting a 2 by 4 or a 1 by 6 is the most common task undertaken with a circular saw, but you can also use a saw for ripping and making dado joints.
  
  

Expert Insight

• This brings us to the subject of changing blades. Always unplug a power saw before you change a blade. This cannot be said enough times. The last thing you need is to have the saw accidentally engaging while you are in the midst of pulling the blade off. Once the power is disconnected, you will first lock the blade (there usually is a device on the saw that does this) and then give the bolt that holds the blade in place a sudden jerk in a counterclockwise direction. If done correctly, the bolt should turn and then eventually come loose. Make sure the bolt is tightened down strong after you change the blade, or the blade will slip.
  
  

Features

• When you cross-cut with a circular saw, always turn on the saw before engaging the blade in the wood. Cut with a steady and thorough motion, and always follow through with your cut.
  
  A circular saw naturally cuts in a straight line, but it is a good idea to use a straight edge (a framing square works well) or a carpenter's square to get a perfectly straight cut. A circular saw and a carpenter's square are a great combination for getting square cuts on framing lumber. Of course, a pencil and a tape measure aren't a bad idea, either.
  
  

Benefits

• This popular tool has become an immense benefit to the building industry, especially in the area of constructing wood frame houses. Carpenters will work all day long with the tool as they first construct the floor, then the walls and finally the roof rafters of a modern wood frame building. Don't forget that its adaptability is just as important, for the circular saw can also be used to cut sheathing, fit trim and even rip a board if necessary. This is why you will never see a builder who lacks one.