| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|
Circular Saws
This is the second power tool purchased for most homes. After you've
drilled a few holes, you'll realize you need to cut things. Folks with a
shop full of tools, will have a circular saw that predates all of their
other tools. It may have been their father's and it probably still works
great. Even if you don't have a table saw, you can rip and cross-cut plywood
and solid wood with precision provided you have a good fence or use an edge
guide with your circular saw. Direct-Drive, Sidewinder, Helical-Drive sawsThat tool you see in the commercials on TV with dad smiling at Christmas after opening his new circular saw is a direct drive saw. Direct drive, sidewinder, helical drive saws have a motor, generally on the right side of the blade, that is hooked up directly or via a simple helical gear from the motor. This is called a left-blade circular saw. It allows you to see the cut line while holding the tool in your right hand. There are right-blade circular saws for southpaws, but the left-handed people we know struggle along with right handed tools. Direct-drive saws are probably the best all-around choice for circular saws. They are lighter weight, come in more flavors and are typically cheaper than worm-drive saws. Worm-Drive, Hypoid-Drive SawsCircular saws using a worm-drive or hypoid-drive provide greater torque than direct drive saws. They are somewhat heavier and more expensive, but are the tool of choice for the construction industry. Because the motor is not mounted on the side of the blade, a worm-drive/hypoid-drive saw is less "handed" than a direct drive saw. A noteable difference between worm-drive and hypoid-drive saws are that worm-drive saws do not use sealed motors and require occasional oil changes. Proponents of worm-drive consider this a plus, since keeping the lubrication fresh can extend the life of a tool under harsh conditions. The tapered, tigher tolerance gearing of a hypoid-drive train allows the use of a sealed motor which does not require oil changes thus reducing maintainance.
In either case, all of these saws provide no compromise raw power and performance. If you
need a circular saw that can rip lumber 12 hours a day without rest, these are the
saws for you. Cordless SawsThe cordless circular saws we've seen are all direct drive. Worm-drive is reserved for saws that require lots of torque and that's certainly not the strength of a battery operated saw. Initially, we scoffed at the idea of using a cordless circular saw, but once we got one (18v Milwaukee 6310-22) it became the first tool we grab for small jobs. For a really big job, we still grab our old screaming monster, but to cut a few boards or rip a sheet of plywood, we use a cordless saw with thin kerf, sharp blade. Cordless technology is evolving rapidly and cordless circular saws can really take
advantage of the extra kick the newer technologies offer. For outstanding performance in cordless saws
you should look at the newer LiIon based battery technology. It promises better capacity,
more power and faster charges. LiIon batteries are lighter weight than NiMH or NiCad technologies
so a 28v Li-Ion pack might not weigh any more than an 18v NiCad pack, but can deliver considerably
more power. Currently Li-Ion systems are more pricey than their NiMH/NiCad brethren,
but if you want performance, they can't be beat.
Plunge Cut SawsThere's been a few times when the ability to plunge a circular saw into
material was very useful. It's often done the old fashioned way of holding
the guard back and tipping the saw into the work piece, but this is not
recommended for safety reasons. The requirement for a plunge cut circular
saw occurs more often in construction (cutting into an existing floor or
wall, for example), than it does in the shop or home, but if you find
yourself in this situation very often, you might consider one. Specialty SawsMetal cutting - Metal cutting saws are designed to run at lower speeds than a standard saw and often have different chip collection facilities than a standard saw. Dry cut masonary/tile - Dry cut masonary saws are usually supplied with diamond blades and are designed to run a much higher speeds than a standard saw. Wet cut masonary/tile - Wet cutting saws are designed to cut masonary, tile, concrete and other
materials where water can be used to cool and lubricate the blade and reduce the dust.
The saws are designed to prevent water from entering the motor and usually have a GFCI plug. Blade SizeThe most popular blade size for circular saws is 7 1/4". Replacement blades are readily available for cutting a variety of materials. You'll get about 2 3/8" of cutting depth from the blade which is sufficient for most materials, but it will require two passes to get through a 4x4. If you want to get through it in one pass, you'll need a larger saw. Each inch you add to the blade size, adds about 1/2" to the depth of cut. It also adds to the weight of the tool and reduces its maneuverability. Smaller saws are handy for cutting plywood and other materials that are
not thick and don't require a great deal of power. They are lighter in the
hand, easier to use, and smaller to transport. Circular Saw FeaturesLaser Guide - Many of the new circular saws come with laser guides. They are cool and can work very well helping you cut where you want. But they aren't a substitute for a straight line and a steady hand. Also, in bright sunlight they might be difficult to see. Carbide tipped blade - Try to get a saw that comes with a carbide tipped blade. If it doesn't, plan to put the steel blade in a drawer and purchase a good blade and factor that expense into your purchase. Carbide blades cut easier and stay sharp much longer than a simple steel blade. Toolless blade change - If you plan to change blades very often, easier is better. Toolless blade changing or at least a spindle lock is handy. Power cord - Most of the less expensive tools go cheap on the power-cord, but many of the better saws have a nice long cord that won't have you looking for an extension on every job. Some tools have removable power cords and others connect directly to your extension cord eliminating the power cord altogether. Electric Brake - Look for a saw with a brake that will stop the blade quickly when the saw is turned off. This makes the tool safer to use and reduces the time you have to hold the tool in your hand waiting for the blade to stop before setting it down. Changeable Brushes - If you plan on heavily using your saw, be sure to check for easily changable motor brushes. Most (if not all) circular saws have changable brushes, but some require disassembly of the saw to change the brushes. Ergonomics - As always, we recommend you check out the tools you are considering purchasing. Be sure to check: visibility of your cut line, weight and balance of the saw in your hand, comfort of the grip, location of the switches, size and stability of the base, ease of use of the depth and angle adjustments and effectivness of the blade guard. Overall Quality - This is a tool that should last a very very long time and be used a good
deal so don't be afraid to pay for a little more quality. You want a good
motor, a solid base and solid adjustments for blade depth and angle. Circular Saws Analysis
Glossary: Table Saw
Glossary: Direct Drive
Glossary: Sidewinder
Glossary: Worm Drive
Glossary: Hypoid
Glossary: Torque
Glossary: Kerf
Glossary: Nickel Metal Hydride
Glossary: Nickel Cadmium
Glossary: Lithium Ion
Glossary: Plunge
Glossary: GFCI
Glossary: Laser Guide
Glossary: Carbide
Glossary: Spindle Lock
|
|
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||