An improperly or poorly sharpened table saw blade can greatly reduce the safety of a table saw. Failing to sharpen your blade can also lead to it wearing out prematurely due to improper cutting angles, which cause the teeth of the blade to become damaged and dull.
Fortunately, a table saw is not too hard to sharpen, and there are many sharpening tools available, including file systems, diamond stones, and carbide blades.
Here are a few tips for properly sharpening a blade.
Steps for Sharpening a Table Saw Blade
1) A carbide blade should be used for steel cutting. If you want to sharpen a carbon steel blade, you must use an aluminum oxide (blue) ceramic brick, which is available at most hardware stores.
Simply put, an aluminum oxide brick (or paper) will work just as well as a diamond stone. Some people believe that the diamond stone is better than the ceramic brick, but I personally have found that the ceramic brick is just as effective as a diamond stone.
2) File systems that can be purchased include wood, leather, and metal files. The diamond file is recommended for carbide blades because it has the best service life and cuts with the highest precision.
You can also file on a flat surface.
3) Try to align the sides of the teeth so that they are all even and line up when looking at them from above. It is best to do this by hand, but you can use a crank handle if necessary.
Be careful not to cut yourself with any unused parts of the blade or leftover bits of tooth sticking up!
4) Make sure your blade is perpendicular to the table, meaning that it is straight (90 degrees) with respect to the table surface. [or it will be bent at 90 degrees]
5) When filing, don’t try to go too deep because this is likely to cause a gouge. If using the ceramic brick, be very careful not to burn yourself when it touches wood (This often happens from the stone touching a piece of metal or one of the table’s sides).
6) If you are sharpening two carbide blades, make sure that both blades are oriented in the same direction and that they are not touching one another.
Also, make sure that each blade is aligned as described above. Their teeth should be even from side to side and even from top to bottom.
7) When you are finished sharpening, make sure to oil your blade (use a silicone-based lubricant) to prevent rusting.
8) If you prefer to use a diamond stone, the carbide blade must be removed and mounted on an adapter. This can be done by using a retaining ring which will only allow the blade to mount on an adapter, not the table saw itself.
9) To mount the diamond stone on an adapter and remove it from the table saw (or vice versa), you must stop the blade before removing/installing it.
If your table saw has a power switch that is separate from the start button, turn this switch off before removing/installing any parts of your saw. Otherwise, you may damage the blade.
10) If you have an old saw with a wooden fence, check to make sure that the teeth are at the proper angle. The teeth should be on a perfect 90° angle when looking from above.
The top and bottom parts of the blade should also be parallel so that it will cut smoothly at about 15° on either side (15° is considered to be very important for cutting and not only for table saws but for all circular saws).
11) If you are planning on making anything from plywood, make sure to get a carbide saw blade. Wood can be cut using a steel blade but only if it is very hard [hardwoods are best for making furniture or cutting boards].
12) The next step is to adjust the blade angle so that it is the same on both sides. Adjusting the angle can be done by turning screws until they line up.
It may take some time to find the exact position of this screw because less than 1/4″ off per inch of saw length can make a big difference in how much material you remove. This adjustment should also include setting the depth of the cut as well.
13) Once you stop the blade, make sure to oil the blade and allow it to cool. The next step is to sharpen the very tips of each tooth so that they are as sharp as possible.
You can sharpen the teeth using either a diamond stone or a file system.
14) Then, you want to sharpen all of the teeth in one go. Simply place your hand on (or move your hand onto) each tooth, move up one tooth at a time, and sharpen all of them in one go.
The apex of each tooth should be perpendicular (90°) with respect to the table surface. This will add a bit of material to the tip and make it very sharp.
15) After you are done sharpening, wipe the blade with a clean cloth. If you want to clean the blade, place a cloth over it and turn the blade upside down (while maintaining the 90° angle) so that it can be dipped into some soapy water. Then dry and oil (don’t use steel wool or abrasives).
16) When using a carbide blade with your table saw, you should use it in conjunction with an aluminum oxide ceramic brick or other diamond stone file system.
Carbide blades are very expensive and tend to dull out very quickly, so you should make sure that you are using them correctly.
17) If a blade becomes too dull, you can use the diamond stone to sharpen it. This will not cause roughness or chipping like other sharpening methods.
18) Another option is to sharpen your blade as described above but then use a file system such as a leather file or wood file to make the tip of each tooth perfect.