On this website, I repeatedly maintain how useful table saws are and how much work you can get done if you learn to use them properly. At this point, we’re going to assume you’ve done your homework and decided on a particular type of table saw, or maybe even a particular model, but your work is not quite done yet. Depending on your projects, sooner or later you are going to have to change the blade from the original one that comes with the table saw when you buy it. The choice of the right blade is crucial, and you will need to consider the type of material you will be cutting as well as its thickness.
Choosing the wrong blade will result in poor woodwork at best, and turn into a potential accident at worst. Now, in order to get the most out of the saw you paid for with your hard-earned cash, and to avoid any saw-related accidents, you need to learn a thing or two about the blades. This short guide I put together should teach you what you need to know. Check it out.
Modern table saws allow the blade to be adjusted in various ways. The blade can be adjusted both vertically and by changing its axis.
Vertical adjustments are made by exposing more of the blade, which changes the depth of cut. This comes in handy for thick pieces of wood as well as for non-through cuts. By adjusting the axis of the blade, you can make cuts at a certain angle, thus making bevel cuts, which are good for creating joints.
In the past, table saw blades were meant to cut only wood, but they are now able to cut through metal, plastic, and other materials. Mind you, most blades are still fabricated out of metal, but some also feature special alloys and materials in the teeth, and various carbon composites for the body.
Before deciding on a blade, you need to look at several characteristics such as its diameter, the material it’s made of, the material it’s designed to cut, number of teeth, maximum speed, and price, among others. Of course, the blade needs to match your table saw as well. Now, let’s see how you do all that.
There are two ways table saw blades are sized: their outside diameter, and the diameter of the mounting hole. Most standard blades for table saws are 8, 10 or 12 inches in diameter, but there are blades as small as 3 3/8 inches in diameter and as large as 30 inches in diameter. The bigger ones are designed for specific commercial purposes, of course, but man, that’s a big blade!
Obviously, the easiest way to know which blade fits your table saw would be to consult the instruction manual. Also, use some common sense. There is a finite amount of space inside the arbor, so you can’t use just any blade. The space is also limited with the presence of a blade guard.
Speaking of the arbor, the central arbor hole on most table saw blades is 5/8 inches in diameter, but then again, there are exceptions to that rule. If the diameter and the arbor are supported by the saw, you are on the right track.
The two basic types of table saw blades are rip and crosscut blades. Rip blades have a smaller number of teeth and larger gullets, which means there’s more room to remove the shavings and dust. These blades are designed to cut along the grain of the material on the table, but although they cut faster, the resulting cuts are rougher.
If finer cuts are what you have set out to achieve, a crosscut blade is the better option. The resulting cut is much smoother, but because the teeth have less space for chip removal and because there are more teeth to cut through the wood, the feed rate is much slower.
If you need both speed and smooth finish, there are combination blades, which attempt to do both. Also, you may come across special cut blades. These are either designed to cut through certain materials like plywood, hardwood, metal, plastic, or even brick, or they are designed to make specialized cuts for the purpose of joint making. This includes sets of dado blades.
The more teeth on a blade, the smoother the cut. The majority of blades have between 24 and 80 teeth, expect for blades specifically designed to cut through certain materials.
Why would you go with more or fewer teeth? More teeth ensures that the cut is smoother, but it also means the cutting will be done more slowly. Fewer teeth means faster cutting, but the cut will be rougher.
A word to the wise: Do NOT EVER attempt to make the cutting faster by pushing the wood onto the blade. The only thing this will do is cause kickback, which will eject the wood back at you at a high rate of speed and potentially hurt you severely. So just be patient.
Blades that are meant to cut plywood and hardwood are usually fabricated out of metal, but those that are designed to cut through harder materials require the use of even harder materials. The harder material is applied around the edge of the blade, with the metal core remaining intact.
For instance, the teeth on blades that cut through wood are made out of steel or carbon steel, which ensures their durability. Then there are masonry blades, which have diamond-tipped teeth, and you can also find blades that are made to cut through aluminum and steel. Such blades have teeth that are treated with hardened metal or tungsten carbide. Finally, there are blades designed to cut through PVC and acrylic materials, which have teeth made out of low-temperature tungsten carbide.
The maximum speed of a blade is usually expressed in RPM (revolutions per minute). One thing you need to look for is the speed of the table saw, which must never exceed the speed of the blade. Blades are designed to rotate at a certain speed, and using it on a table saw which exceeds that speed will cause the blade to break apart due to centrifugal force.
This is pretty much everything you need to know about blades. If you decide you want to learn even more about blades and their properties, this should serve as a good base for you to build upon.