A circular saw's large blade and loud sound can be intimidating to the newbie DIYer, but don't let that scare you away from one of the most useful power tools in any workshop.
The circular saw is the most ubiquitous power tool around. You'll see it at every construction site, as its applications are numerous. Many home maintenance and building projects will also benefit from having a circular saw available. From ripping sheets of plywood to cutting 2x4s, a good quality circular saw will make short work of all types of wood.
Corded Versus Cordless
Circular saws, like most other power tools, come in corded and cordless options. A few years ago there would be no debate, as cordless circular saws couldn't deliver the raw power, blade speed, and runtime that is required on jobsites. Battery technology has advanced rapidly, though, and the introduction of brushless motors has put a few cordless circular saws on the map. Corded saws remain cheaper, however. Unless mobility is a top priority, going corded can save you quite a bit.
Sidewinder Versus Worm-Drive
Circular saws are divided into two major categories: Sidewinders (direct-drive shown above) and worm-drive units. On a sidewinder, the motor sits directly next to the blade which makes them small, lightweight, and ideal for tasks around the home. Worm-drive saws create more torque due to a beefy spiral gear that transfers power to the blade more efficiently as the motor sits behind the blade.
Carpenter Robert Robillard states: "Worm drive saws are unmatched for their line of sight and blade visibility (blade on left for right handers) as well as their ample power. Today's worm drives are lighter due to magnesium materials. Many carpenters who do rafter and stair work would have a worm drive and a side winder for the opposing bevels. I personally own both and if I'm making a few cuts I use the lighter sidewinder. If I'm on a framing job -- it's the worm drive."
Worm drive saws like this SKILSAW are more expensive than comparable sidewinders, but the added torque and heft can help drive through tougher materials.
The alternative to these styles of circular saws are the compact trim saws. They are available corded and cordless and can provide ample cutting power for jobs around the house. They are much lighter and easier to manoeuvre in tight spaces.
Before buying a saw, make sure you get your hands on it. Take note of the weight, balance and grip size. Hold a bunch of different saws and you'll know which are more comfortable than others. For cordless try to hold one with a battery attached as that changes the weight and balance considerably.
As with any power tool, safety comes first. Always wear proper eye protection and read through the safety manual that comes with your saw. Norm Abram of This Old House offers these great tips for setting up a circular saw and how to properly make cross-cuts and rips (sawing with the grain).
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