Circular Saws
What is a circular saw?
A circular saw is the portable version of a table saw or radial arm saw. It features a circular blade with saw teeth around the outside edge. The saw's motor spins the blade at an average of 5,000 rpm. The blade base can be adjusted for depth of cut and bevelling. Used for crosscuts and rip cuts, the circular saw's base plate can be adjusted to make angle or bevel cuts (up to 51 degrees on most 7-1/4 inch models). The circular saw typically is subjected to rougher treatment - more than any other portable power tool - and frequently requires heavy-duty features such as beefed-up horsepower, carbide-tipped blades and rugged gears.
What types of circular saws are available?
There are two main types:
1. Worm-drive saws.
These saws feature a motor mounted behind and transverse to the saw blade. The blade is positioned on the left side of the motor, making it easier for users to see the cutting line. The worm-drive saw is typically more powerful, but also heavier than other models.
2. Sidewinder saws.
Sidewinders are typically lightweight and portable, and have motors mounted directly on the side of the blade. They are the most popular circular saw models because they weigh less but still have enough power to handle most woodcutting tasks.
What do circular saws cost?
Like many other portable power tools, circular saws vary in price. The amount you spend on a circular saw will depend greatly on the type of model you choose and the specific features and benefits it offers.
What types of saw blades are available?
Circular saw blades come in a variety of sizes and constructions and have a number of different applications. Blade sizes (the diameter of the blade) typically range from 3 3/8 inches to larger than 15 inches. The most common blade size is 7 1/4 inches.
Typical blades include:
- Steel blades, which are generally the most economical material. Steel blades require frequent sharpening and offer a shorter lifespan than other types.
- Carbide-tipped blades, which, depending upon the type of the materials you cut, can last up to ten times longer than steel blades.
Dyanite® carbide-tipped blades, which generally offer two to five times longer cutting life than standard carbide-tipped blades.
- Bonded abrasive blades, which are commonly used for cutting metal and masonry materials.
Whatever the blade material, there are three classes of circular saw blades. Blade class is determined by how the blade body avoids binding and clears through the workpiece.
1. Set-tooth blades.
Flat-ground with teeth that are alternately bent to one side or the other to create additional width at the tips. Kerfs are about 1/8 inch on larger teeth, 3/32 inch on smaller teeth. Teeth need to be kept sharp and properly set or the blade will wander from the cut line and bind. This class of blade is easy to recondition.
2. Hollow or taper-ground blade.
The sides of the blade are ground to leave tooth edges wider than the blade's hub. This class of blade cuts smoother than equivalent set-tooth types.
3. Tipped-tooth blade.
These blades have brazed-on tungsten-carbide tips that are slightly wider than the blade. Tips may be flat-ground (straight across) or bevelled in alternate directions. Such blades wear longer than the other types. They are especially good for making deep cuts or cutting into hard, knotty woods. Carbide-tipped blades should not be used to cut ferrous metals or masonry. If dulled or damaged, tipped-tooth blades can only be reconditioned professionally.
In addition to blade class, the size and shape of the blade teeth and gullets determine the kind of work a blade can do. Individual features determine the quality of a blade's cut and its durability.
Blades are designed for a variety of work:
1. Rip cut/ripping blade.
Designed to create a straight cut that runs the length of a wood board or with the wood grain.
2. Crosscutting blade.
Cuts across the wood grain and is commonly referred to as a mitre, bevel, compound (mitre and bevel) or straight crosscut.
3. General purpose/combination blade.
Designed to handle both crosscut and rip cutting with any type of saw.
4. Finish/trim blade.
Provides a clean smooth finish for fine woodworking and trim work.
5. Specialty blade.
Designed to cut a specific material or provide a specific quality of finish (i.e., a masonry blade is used for cutting stone or concrete).
If your blade is aligned, but it still burns or mars the work or wanders from the cut line, the feed is too slow, too fast or the blade is dull. Or you may have chosen the wrong blade for the type of cut you're making or the material you're cutting.
Purchasing Tips
Ask yourself these questions when choosing a circular saw...
You can narrow down your circular saw choices by asking yourself some basic questions. Your answers can help you choose the model that best meets your needs.
What type of projects do you plan to use the saw for?
Sidewinder saws and saws with the most common blade size (7-1/4 inches) can usually handle most medium-sized construction tasks, including cutting lumber and plywood two-by-fours for general carpentry, framing and finish work. Large jobs like cutting construction posts and beams typically require a saw with a larger blade (at least 12 inches in diameter). In general, worm-drive models are more powerful and can muscle through cuts that might stall a lesser saw.
How often will the saw be used?
Your answer will determine how much power you will need in a circular saw. Sidewinder saws can typically handle occasional jobs around the home, while worm-drive saws are generally better suited to bigger jobs and tougher materials.
Who will be using the saw?
Will you be the only one using the saw or will it have other users as well? Be sure to consider the potential saw users and their ability to safely operate the saw. In general, powerful saws are heavier than weaker ones. So, worm-drive saws tend to be heavier than sidewinders, and can cause more user fatigue over time.
Consider these important circular saw features...
Power. A circular saw's power is measured in amperage. In general, the higher the amperage, the more powerful the saw. Professional quality 7-1/4 inch saws typically feature motors that work between 13 and 15 amps.
Weight. As a rule, powerful saws tend to be heavier than weaker ones. Be sure to choose a saw that you can lift and operate easily.
Handles. The style of the handle determines how easy it is to safely control the saw. Be sure to choose a grip style that you can handle and one that is comfortable to use.
Adjustable cut depth. An adjustable depth allows you to use the saw for a number of different cutting applications and is a necessary feature for cutting small grooves.
On-board wrench storage. This feature keeps the tool close for quick blade changes.
Dust collection port. Because saws can produce a considerable amount of sawdust, look for a model that provides a dust extraction hook-up (typically for a shop vacuum).
Electric brake. This feature stops the blade shortly after your hand comes off the trigger - making it a safety feature and a time-saver.
Arbor lock. Makes blade changing quick and easy.
Don't forget the extras...
When purchasing a circular saw, don't forget all the items that you may need.
For proper operation of a circular saw you will need:
- Task-specific blades. For safe operation of a circular saw you will need:
- Safety goggles or glasses.
- Dust masks to prevent you from breathing dust created while sawing. You may want to consider the following circular saw accessories, as well:
- A rip guide on 7-1/4 inch models, to assist in creating straight rip cuts.
- A circular guide master, to help you make straight, angle and bevel cuts. It also allows you to transfer measurements.
- A carrying case, to help protect the tool from damage.
Product Maintenance and Cleaning
Having your saw repaired
Check your sales receipt to find the date you purchased the circular saw, then look in the owner's manual to see the length and details of the warranty. If you need service, you can call 1-800-4-MY-HOME® (1-800-469-4663) for the Sears Parts and Service location nearest you.
General maintenance tips
- Inspect the saw for frayed cords, loose or broken parts/switches and other obvious problems before each use. If anything is damaged, have the tool serviced before you use it.
- Do not attempt to repair a cracked or broken part. This could result in a part that will no longer operate as designed, placing the user at risk.
- Follow the lubrication guidelines in the owner's operating manual.
- Keep any safety devices clean.
- Use only accessories that are recommended by the manufacturer for your particular saw.
- Do not expose the saw to rain or wet conditions.
- A battery-powered saw must be recharged only with the specified charger for the battery. A charger suitable for one type of battery may create fire risk when used with another.
- Use the battery-powered saw only with the specifically designed battery pack.
- When the battery pack is not in use, keep it away from other metal objects (coins, nails, screws, paper clips, etc.) that can make a connection from one terminal to the other.
- Keep the saw's cord away from heat, oil, sharp edges or moving parts.
- Do not wrap the cord around the saw for storage.
- Clean the unit using a damp cloth and mild detergent.
- Cover the saw and store it in a dry place.
Product Safety
Before operating
- The best time to consider safety is before you purchase a saw. Make sure you can physically handle the tool before purchasing it.
- Read and understand the owner's operating manual. Learn where the controls are and what they do.
- Ensure work areas are free of clutter and have adequate lighting.
- Ensure that the blade you have chosen is sharp enough to do the job.
- Sharp blades work better and are much safer than dull blades.
- While the saw is still unplugged, set and lock the depth of the blade so that the lowest tooth does not extend more than about 0.3 cm or 1/8 inch beneath the wood.
- Always secure your stock before cutting.
- For best control, keep the saw's handle dry, clean and free from oil and grease.
- Do not remove or disable safety guards or devices.
- Do not carry a corded saw by the cord.
- When plugging a saw into an outlet or connecting a saw to an extension cord, be sure the power switch is in the "off" position.
While Operating
- Always wear the proper clothing and gear when operating the saw. This includes safety glasses, ear protection, gloves, face shield, dust mask and appropriate footwear. Avoid wearing loose clothing and jewellery. If your hair is shoulder length or longer, tie it back.
- Keep all bystanders, children and pets clear of the work area.
- Always use two hands when operating a circular saw.
- Be sure to keep your hands clear of the saw blade at all times.
- Be sure both ends of a board are well supported. Do not cut between the supports.
- Kickback can happen to even the most careful users, but it can be minimized by properly setting the blade depth, standing in the right position and ensuring the work is held securely.
- Use caution when ripping small, narrow pieces. Clamp them securely in place before cutting.
- Know how to stop the saw quickly, if needed.
- Do not force the saw during cutting.
- Do not cut materials without first checking for obstructions or other objects such as nails and screws.
- Do not overreach. Maintain the proper footing and balance when using the saw.
- When using a corded saw, use grounded extension cords and always saw away from the cord.
- Do not use an electric-powered saw in damp or wet locations.
- Make sure that the retracting lower-blade guard has returned to its starting position before laying down the saw.
- Never unplug a corded saw by pulling on the cord.
- Do not use a saw with a cracked or damaged cord.
- Never leave an idle saw unattended.
- Be sure to turn off and unplug a saw before changing blades or accessories.
- Only use the saw for the job it was engineered to do.
- Do not operate a saw when you are fatigued or under the influence of drugs or alcohol.
- Do not operate power tools in the presence of flammable liquids, gases or dust. Some tools create sparks, which could cause a fire or explosion.