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Before You Buy a New Table Saw...The table saw will become the heart of your shop and that is why you might want to take the time to carefully consider what you are about to purchase before laying down your hard-earned cash. There's a lot to know about one table saw as compared to the next. The aim of this piece is to guide you successfully along the path to finding the right machine for you. After all, nothing less will do! There are many things you will want to ponder before purchasing a new table saw for your shop. There are three main types of table saws: (1) the lightweight, inexpensive and portable contractor’s saw, (2) the cabinet saw, so-named because it has an enclosed cabinet as opposed to open base and (3) the new breed of so-called “hybrid” table saws which fill the price tag gap between contractor’s saws and cabinet saws. This discussion will be only concern cabinet saws because, in my experience, nothing less will do for a shop that engages in fine woodworking. Smaller saws lack both the accuracy and capacity of cabinet saws. The table saw is the nucleus of your shop. You will use it more than any other tool and its precision and capacity will determine the quality and size of what you will be able to produce. This is comparable to deciding on someone to marry: Ideally, it’s for a lifetime and you will have to live with your choice for a long time to come. Therefore, rushing into purchasing the first table saw you see, without doing your homework, is like a quickie Las Vegas marriage, always a bet. There are numerous features you should before investing your hard-earned dollars in any particular table saw. As I have stated again and again, any woodworking machine you buy should be just slightly more capable than what you will demand of it now or what you imagine you would likely to demand of it in the future. While cost is important, affordability should not be the sole determining factor in your buying decision. If you can’t pay for the saw you need, wait until you can. Don’t saddle yourself with a table saw that may drive you crazy every day of your life. Take a few moments to consider what you really require and which machine will best fill the bill for you. I’d like to take a minute to talk about the features that you should be looking for and what these features will mean to you after you unpack and set up your new table saw. These features include: Motor horsepower, blade size, trunnion construction, tabletop flatness, tabletop size, arbor size and arbor bearings, sawdust extraction, ease of operation including raising, lowering and tilting the blade, tilt of the blade (left or right), the necessity of a magnetic switch and the importance of its location, ease of access to the interior of the cabinet, accuracy and ease of operation of the fence, the amount of rip space to the right and the left of the blade, safety features and table saw mobility around the shop. In addition to the table saw itself, you may want to fabricate an outfeed table around the rear of the saw, if space permits. We’ll talk about that, as well. MOTOR HORSEPOWER Motor horsepower and blade size are closely related. The larger the blade, the more horsepower will be required to cut, at full blade height, through a piece of lumber. Too much power is never a problem. Too little power can cause the saw to bind, slow down and even stop in the middle of a cut. This is not acceptable, nor is it safe. The smallest motor I would even buy for a 10-inch saw would be 3 horsepower. For a 12” to 14” saw it would be 5HP and for a 14” to 16” saw, I’d prefer 7.5 HP. You will also need to consider if the saw motor is single or three phase. Three- phase motors use electricity a bit more efficiently. If you don’t have three phase power at your woodworking shop, however, you will either have to buy single- phase motors or purchase and install a phase converter large enough for your three-phase saw motor. Most saw motors use 230 or 460 VAC power, so make sure you have available in your shop the voltage your saw will require. Three- phase motors can run on 208 to 220 volts or higher, depending on the motor.
The trunnion is the mechanism inside the cabinet which is responsible for both raising and lowering the blade and tilting the blade for bevel cuts. It is manipulated from the outside of the saw by two separate wheels or cranks: One for raising and lowering the blade (usually found on the front of the cabinet) and the other for tilting the blade (either left or right, depending on the saw) which is customarily, but not always, located on the side of the cabinet. The trunnion determines the precision of your cuts so you want to be certain that it is well built and accurately machined. The saw blade must always be exactly where you require it to be. Furthermore, the trunnion must be easy to operate. It should not require Superman to raise or tilt the blade. As time goes on, you may find that it is harder to turn the wheels or cranks that move the trunnion. This is usually because of sawdust contamination of the gears and/or lack of lubrication. Some better saws have ways of stopping sawdust from the cabinet into an external dust port before it can get into the gears. Other saws come with self-cleaning gear teeth.
One table saw maker I know believes in “aging” its cast iron machine table tops before milling them flat. The tops are cast and then left outside in a “bone yard” to bend, bow, warp and twist in the sun and rain for a year or so. Then, they are brought inside where all the rust is removed and the table top is ground absolutely flat and polished to sheen. The premise is that the table top needs to settle into a place where all post-casting movement has ceased and that the table should not be ground flat before this is done. Otherwise, the table may move out of absolute flatness after it is part of your new table saw and that it not at all preferable. Why? Because the flatness of your table saw top will determine the accuracy of your cuts. Be sure to check your new table saw for table flatness with a straightedge on or before delivery and afterwards from time to time. Lay the rule across the table top at all angles and check for daylight under the rule or rocking of the straightedge on the table top. The dimensions of the cast iron table saw top are also significant: The larger the better. When you are sawing large objects, you want as much flat table surface as you need to support the wood flat to the blade for precision. Larger table size is usually accomplished by attaching cast-iron table wings to the edge of the main table. These wings must be as flat as the table and the seam they create must be aligned so that the top of the wing is flush to the table saw table along its entire length.
The saw blade is mounted on an arbor with an arbor nut and the arbor is turned by the motor usually via pulleys and 1 to 3 V-belts. The arbor is mounted into the trunnion inside two or more arbor bearings. These should be sealed from dust for obvious reasons. The size of the arbor determines the dimension of the hole in the middle of the saw blade. This is usually 5/8” for a 10” blade and 1" or larger for blades larger than that. The strength and alignment of the arbor and the bearings which support it determine the accuracy and smoothness of the table saw. Vibration and noise should be kept to a bare minimum and the saw blade should be straight in the table from front to back at all elevations and bevel angles.
Most table saw trunnions are made to tilt either left or right (but not both) to a maximum of 45 degrees from vertical. If you have a choice, and you usually do, never buy a right-tilt saw for the following reason. A right-tilt saw tilts the blade towards the fence and can pinch a work piece into the fence, causing a jam or, worse, a kickback just as the cut is finishing. Further, on a right-tilt saw, the blade is leaning towards the fence and could cut into and ruin the fence if the fence were to be inadvertently moved too close to the spinning blade. A left-tilt saw tilts away from the fence and instead of pinching the work piece, allows it to rise vertically slightly, when required.
There is a rule that says, “Never stand directly behind a horse or a table saw.” Sooner or later every table saw operator will do something stupid that causes a kickback. If the worker makes it a practice to avoid standing where the kickback will occur behind the blade, he or she will probably avoid the severe injury that can be inflicted by a flying piece of wood striking the face, neck, chest or arms of the woodworker. There are many hold-down and anti-kickback devices on the market. Some are beneficial and some are a disaster in themselves. I had a large metal combination hold-down and anti-kickback device get caught in the saw blade, ripped off the fence to which it was clamped and flung into a plate glass door behind the saw. I heard it go whistling past my right ear. It missed me because I was standing, as always, well to the left of the saw blade. Woodworking can be a dangerous business. Always use a push stick or similar aid. Fingers are not replaceable. Never try to rip skinny strips next to the fence. Instead, cut them off of the left side of the work piece. In this case, you would stand to the right of the blade. In short, think ahead about the possible complications of what you are about to do, keep your eyes wide open (wearing goggles, of course) and keep your wits about you at all times. Another important safety device is the magnetic switch. This device protects you after an electrical power outage. If the power fails and you have a regular switch, the saw will come back on when the electric power comes back on. If you were to be near the blade at the time, this could be disastrous. A magnetic switch will not allow the saw to start again until you press the button. The location of the switch is also important. It should be right out front where it can be quickly accessed by a hand, foot or knee in the event of an emergency. The off button should be wide, red in color and should extend outside of the switch box like a mushroom for fast access.
My dream would be to never have a speck of dust reach the gears of my table saw trunnion and that all sawdust would be sucked away from the saw blade and out of the machine as soon as it was created. I would never need to clean out sawdust from inside the saw cabinet and the trunnion would always operate smoothly and easily. While I don’t expect to ever see my dream fully realized, there are saws on the market today that closely approach this level of efficiency in sawdust ex traction. Some saws shield the blade in a casing underneath the saw table and vacuum the dust out directly from there. Others slant the floor of the saw cabinet towards a dust collection port. Many just allow the sawdust to accumulate on the floor under the saw until you clean it out. You will always have some cleaning of the interior to do. Perhaps you won’t wait until the sawdust has totally encased the trunnion gears packing itself up to the bottom of the table top. You will have to connect the saw to a dust collector through its dust port. The suction of the dust collector should be about 350 CFM for a 10” saw and more for a larger saw.
At least one, but preferably two or more access doors should be present, opening into the cabinet of the table saw. The door you will use most frequently will be for cleaning out the interior of sawdust. Another door should give easy access to the motor, trunnion and belts for adjustment and repair. Many table saws provide a removable access panel instead of a second door. That’s fine for occasional motor, arbor, belt and trunnion access but you will need the sawdust door to open and close straightforwardly. THE FENCE The saw should be sold with a Biesemeyer or similar type fence included in the purchase price. This type of fence locks and aligns itself to a rectangular tube attached to the front of the saw table when you press down on a handle. Fence precision and ease of operation will be critical every time you touch your table saw and so a cheap fence is no bargain. The fence will probably read measurements along a stick-on measuring tape on the top of the front fence rail tube. You will have to carefully adjust the fence for consistent accuracy. Instructions of how to do this should come with the set-up instructions for the saw. The fence must be aligned so that the front of the blade and the rear of the blade are exactly the same distance from the fence at all settings. Once you have determined that the blade and fence are parallel to each other, you must cut some test boards to correctly set the fence to the scale. Set the fence to exactly 2” on the measuring scale. Rip a test board and measure it. Adjust the fence to the scale by positioning the viewer’s hairline left or right. Rip more boards until you have exact accuracy. The viewer through which you see the tape should be strong in magnification.
Your new saw must have a rip capability equal or wider than the widest wood or plywood you will ever want to rip. Usually, a cabinet saw will have a rip capacity of around 30 inches or 50 inches. A large rip capacity to the right of the blade will require an extension table to support any work piece wider than the cast iron table. Often, this extension table is included with the saw or, otherwise, you can definitely build your own. The fence must have a tube or rail long enough to achieve the maximum width you want to rip. Since you know that a sheet of plywood measures 48 inches in width and 96 inches in length, I would think that you might want to opt for a 50-inch rip as opposed to the slightly less expensive 30 inch rip capacity. You might be required to rip off only one inch from that sheet of plywood and, while doing that, you will want the plywood to be fully supported. You might want to crosscut a sheet of plywood into two 48” pieces. You also should consider the rip space to the left of the blade: The wider, the better. Sometimes, you might want to undertake tasks that require the fence to be put over to the left side of the blade.
Some shops are small enough to require that all machines be able to roll around on the floor. The premise is that you pull out only the machine you are utilizing at the time. In planning your shop, you should decide if your space requirements will mean that everything has to roll, some machines but not others have to roll or all machines can remain in their own positions permanently. Many cabinet saws offer the optional extra of some sort of mobility device. In the case of a table saw, you don’t want it rolling around while you are pushing lumber through it and so the wheels must retract enabling the saw to rest on its cabinet base on the floor. Some of the nicer table saws have the caster wheels permanently mounted inside the cabinet so they are never seen and are never in the way. A foot pedal controls elevating the saw into the mobility position and then lowering it back down onto the floor. If your table saw does not have this feature, after-market mobility bases can be purchased as needed.
A perfect solution is to have enough shop space so that you will never have to move your saw around at all. In this situation, you can make an outfeed table to support large work pieces and long lumber as they leave the back edge of the table saw table. In the best situation, depending on space available, you should make this outfeed table so that it extends eight feet or more in back of the blade. You can use the space below the table for board storage and/or drawer space. The table can also serve as a work bench for the fabrication of large cabinets and tables. You can use it for pipe clamp glue-ups and spray painting layout, as well. Needless to say, the outfeed table must be accurately adjusted to the same height as the top of the table saw table and you may need to extend the slots for the miter gauge into the beginning of the top of the outfeed table. If your saw extension table extends 50 inches or so to the right of the blade, so should your outfeed table and it should extend along the entire back edge of the table saw to the left of the blade. The saw should ideally be positioned so that you can bring long lumber through the shop door and directly onto the saw table without having to turn a corner. If you keep what you have read here in mind, you should be able to find a machine that is just the thing for your needs. Remember, cheap price guarantees neither satisfaction nor success.
Bob Gillespie TABLE SAW REVIEWS: WOODWORKING TOOL REVIEWS; © 2010 Robert M. Gillespie Article Tags: Table Saws, Cabinet Saws, Magnetic Switch, Outfeed Table, Phase Motors, Cast Iron, Work Piece, Extension Table, Might Want Source: Free Articles from ArticlesFactory.com
ABOUT THE AUTHORBob Gillespie has been a woodworker since 1981. He founded Craftsman Woodworking in Hawaii where he was involved in company administation, furniture design, prototype manufacturing and sales. He is also an experienced advertising copywriter and author.
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