Lucile Lewis Table Saw August 23rd, 2018 - 03:32:02
There are many things you will want to consider 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 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 produces fine woodworking. Smaller saws lack both the accuracy and capacity of cabinet saws.
One drawback of lighter-weight table extensions is that they have less mass, and the overall mass of the saw is what soaks up the vibration crated by the motor and other moving parts. The added mass of heavy cast iron extension wings decreases vibration, which in turn helps the saw stay in calibration, and also helps it stay planted firmly on the shop floor. On less expensive saws, extensions made of stamped metal, or ones that aren't precision ground, can also compromise the overall flatness of the table surface.
The smallest motor I would even consider 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 like 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 location, however, you will either have to buy single phase or purchase and install a phase converter large enough for your 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.
Some saws shield the blade in a casing underneath the saw table and suck 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 need 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.
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 size 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 minimum and the saw blade should be straight in the table from front to back at all elevations and bevel angles.