Choosing a Circular Saw

The circular saw is a must-have power tool for home and professional workshops. It has a toothed disc that acts as a cutting blade as it spins in a circular motion around a mandrel. Equipped with the right blades, it can cut through wood, steel, ceramic tile, plastic, and masonry. A circular saw is useful for carpentry, metalwork, and DIY home installations.

When selecting this type of saw, it’s best to consider factors such as blade size, ergonomics, and the kinds of tasks you may encounter. This circular saw guide explains important things to know about the power tool.

Styles of Circular Saws Available

There are two broad categories of circular saw: worm drive and sidewinder models.

Worm Drive Saw: The heaviest and most powerful circular saws belong in this category. A worm drive saw has its motor mounted parallel to its blade. This arrangement allows it to generate enough torque to cut through very hard materials, such as concrete. The saw also has a handle set farther back to minimize the kickback from the high torque produced by its motor.

Sidewinder Saw: This is a lighter unit and easier to handle than a worm drive saw. It’s the circular saw favoured by many homeowners and commonly found on construction sites. A sidewinder saw has a motor mounted at a right angle to its blade. This design improves manoeuverability and delivers enough power for most cutting tasks.

Trim Saw: This is smaller than a sidewinder saw but has limited function. It’s a lightweight power tool best used for panelling and other finish carpentry tasks.

Like most power tools, circular saws are available in corded and cordless models.

Corded: The main benefit of corded saws is their unlimited run time. They’re usually more powerful than cordless units. These circular saws typically have power ratings between 10 A and 15 A. The higher amperage translates to faster cutting action and smoother cuts. A corded saw may require an extension cord to connect to a wall outlet. Hooked to a constant power supply, it can run for as long as needed and doesn’t require replacement or recharged batteries. On the other hand, a power cable and an extension cord tether this power tool and limit where you can use it. Cords and cables may also restrict manoeuverability.

Cordless: The greatest advantage of cordless circular saws is their portability. Without power cables and extension cords, they’re suitable for use anywhere. Since they’re smaller than corded models, these tools are also ideal for working in confined spaces. It’s important to consider battery power and capacity before adding these machines to your cordless power tool sets. Units with batteries rated above 18 volts are more powerful than those with 14- to 18-volt batteries and better suited for more demanding jobs.

Circular Saws for Different Applications

Finding the correct saw for a cutting task is an important first step if you hope to complete the task in record time. The right tool for a job isn’t always the most powerful saw or one with the biggest blade. Establishing where and how often you intend to use the tool helps when considering how to choose a circular saw. It also helps to think about the kinds of materials you plan on cutting.

A sidewinder saw is an excellent choice for most cutting tasks involving wood, wood products, sheet metal, and cement board. A cordless sidewinder unit may be the right tool if you only require a circular saw occasionally and don’t cut a lot of materials. Having extra batteries charged and on hand helps reduce downtime when cutting hard materials that can drain battery power more quickly.

In most cases, a worm drive saw is the more effective tool for cutting materials harder than wood. It’s also suitable for intensive operations and professional use.

Parts of Circular Saws

A basic understanding of circular saw parts is useful when comparing different models while shopping for this power tool. Note that not all the parts and features described below are available on every model.

Handle and Trigger: The handle provides a secure hold while using and transporting the tool. The trigger starts and stops the circular saw. It usually sits close to the handle where the operator can push it with an index finger.

Front Grip: A grip that serves as a secondary handle to hold the tool more securely and dampen kickback while it’s running.

Blade: The cutting disc of the saw. The most common blade for a corded circular saw measures 7 ¼ inches in diameter. Cordless models usually have smaller circular saw blades than corded models.

Retractable Lower Blade Guard: An essential safety feature that rolls back when cutting with the saw and snaps back in place when cutting is done. It protects the teeth of the blade from damage and protects users from accidentally cutting themselves on the blade.

Safety Switch: Prevents accidental start-ups. To start a circular saw‘s motor, the user must press the trigger and safety switch at the same time.

Notch: A small V-shaped notch at the front of the plate that helps guide the saw blade along the cutting line.

Motor: An electric motor that drives the blade. A couple of circular saw tips to note about motors: first, a more powerful motor cuts faster and easier but also makes the saw heavier. Secondly, motors with ball bearings are more durable and more precise than those with bush bearings.

Base Plate: A rigid plate that supports the weight of a circular saw while cutting and can also help vary cutting depth and angle. High-end models use aluminium and metal alloy base plates. These are lighter than steel base plates.

Plate Tilt Adjustment: A bolt that fastens the sliding plate at a preferred angle. Both circular saw parts allow the tool to adjust to a 45-degree cutting angle during bevel cuts. Select models can tilt up to 56 degrees.

Locking Knob and Rip Fence Slot: The locking knob secures the rip fence to slots in front of the saw. The rip fence is for improving cutting accuracy and the knob and slots ensure it fulfills this function.

Pro Tip

If you prefer cleaner cuts than your saw blade can manage, it’s a good idea to try replacement blades with more teeth before considering upgrading to a more powerful saw.

Features of Circular Saws

While corded and cordless models share most circular saw features, a few are unique to either type of cutting saw. It’s a good idea to look for these key features before making a purchase.

Power: Manufacturers rate the power outputs of corded saws in amps and use volts for cordless models. Corded units are available with power ratings from 10 A to 15 A, while the range for cordless saws is 14 to 36 V. For most users, 13-amp corded saws and 18-volt cordless units offer excellent power-to-weight ratios.

Blade Size: Also referred to as blade capacity, this describes the diameter of a saw’s blade. The standard 7 ¼-inch circular saw blade can cut through materials that are 3 inches thick. It’ll cut through 2-inch lumber at a 45-degree angle in a single pass.

Electric Brake: This reverses the flow of electricity passing through the tool’s motor to quickly stop the blade. Saws with this feature can stop spinning their blades in under 2 seconds, much faster than those without the feature.

Spindle Lock: It locks down the saw’s shaft and blade to make changing the blade easier and safer.

Laser Guide: One of the optional circular saw features found in high-end models, it shines a laser beam that acts as a cutting guide.

Pro Tip

Try to avoid preventable accidents like electric shocks by disconnecting power tools after using them. It’s also advisable to unplug corded saws and remove the batteries of cordless units when servicing them.

Blades Make Circular Saws Versatile Tools

Replacement blades are the most important accessories for power saws.

Most manufacturers include all-purpose wood-cutting blades with their saws. Besides these, there are other types of blades that can make circular saws more useful. These include blades suitable for cutting metal, stone, tile, and concrete.

Sidewinder and worm drive saws equipped with the right blades can replace some specialized saws in a pinch. For example, while wet saws are better for removing porcelain and ceramic tiles, circular saws equipped with tile and paver saw blades are good substitutes.

It’s a good idea to confirm that a new blade will work with your saw. When shopping for these power tool accessories, you’ll find other options besides regular steel blades. High-speed steel blades are harder, sharper, and stay that way for longer. Carbide-tipped blades stay sharper even longer. Diamond-tipped blades are harder than steel and carbide ones and ideal for cutting tiles.

Other circular saw accessories to consider adding to your kit include dust bags and chutes, metal carrying case, parallel guide, lubricant oil, and splinter guards.

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