The circular saw is an all around general purpose tool that every carpenter or woodworker must have in their arsenal of equipment. A circular saw should have the horsepower to cut smoothly through lumber without slowing down, choking, or binding up on the wood. If your circular saw does not have the power to cut smoothly, your blade will quickly overheat and dull.
When you are shopping for a circular saw, it is easy to be misled by the statistics listed on the packaging. The amps that a motor consumes is not actually indicative of how much power it will put out, and nor is the horsepower rating of the motor. Although horsepower may seem like a good straightforward benchmark of how strong a saw will be, it can also leave you falsely informed. Other factors such as the gears of the saw can influence the actual power output. The old adage that you get what you pay for really applies here, and is a more accurate guide to a saw’s power than any of the other numbers. Plan on spending at least $100 here, or more if you can afford it.
Circular saws also come in a number of different types. A worm drive saw will provide the most raw power, and is an appropriate choice when cutting through heavy lumber or concrete. Worm drive saws are fairly heavy, however, and can be tiresome for longer jobs. A sidewinder saw is significantly lighter than a worm driven saw and can be a good choice for longer jobs. There are also cordless saws out there, but they have limited battery lifetimes and the cutting power of most of these saws can’t compete with a plugged in saw.
When using a circular saw, be sure that the blade depth is set properly for the work that you are doing. The bottom most tooth on the blade should sit about 1/4 inch below the workpiece. Sit your workpiece across two sawhorses or other such supports, leaving the waste ends free to fall once the job is done. Be sure to unplug the saw whenever you need to make any adjustments.
There are a number of circular saw manufacturers out there. Milwaukee and Makita provide good saws for affordable prices. For a good cordless saw, Bosch provides several dependable models.