How to Sharpen a Circular Saw Blade – A Step-by-Step Guide

A circular saw is a portable or table-mounted tool used to cut many different types of materials, such as metal, plastic, wood, and masonry. It is among the most useful tools for woodworking.

A sharp enough blade will maximize the cutting performance as well as the precision of your woodworking. Circular saws feature a disc or blade with teeth on the edges. These blades of the circular saw are made by using high carbon steel. The circular saw motor spins the blade at high speeds, allowing the teeth to cut through materials smoothly.

A worn-out blade on a circular saw leads to chipping, grain breakage, and blowout.  Furthermore, a dull blade slows down work and can even be dangerous as it can overheat, create rough finishes, and even cause kickbacks.

Making sure your blades are appropriately sharp, will prevent excessive material waste and potentially hazardous working conditions.

Should A Circular Saw Blade Be Sharpened?

Before we go any further, should these blades be sharpened? When your current blade becomes dull, why not just get a new one? Unfortunately, circular saw blades are fairly expensive.

Costly Saw blades mean replacing them is not easy and cost effective. With a little sharpening, your blade will be sharp like a new one. Sharpening the blade will prolong the blade’s life.

In addition to giving you a rougher finish, a dull circular saw blade causes your motor to work harder and potentially burn out sooner. In the long run, sharpening your saw blades will save you money because you’ll get better cuts and require fewer replacements for your saw and blades.

So, is it possible to sharpen the blade in your saw multiple times? It depends upon the kind or type of blade you are using. On average, you can sharpen a circular saw blade 3-4 times if done yourself.

What Are the Signs of a Dull Circular Saw Blade?

Several signs will indicate that teh blade of your tool has started getting dull:

The first sign is to be checked in the quality of cuts that your circular is making. Dull blades fail to provide smooth cuts. This may affect your projects’ outcome.

You can tell if the tool is working harder by hearing the sound that the motor makes and the blade sounding different. Your circular saw will need comparatively less power if it is sharp enough. In addition, it also operates quietly.

Another indicator that your blade needs to be sharpened is when you have the frustrating experience of material cracking off. It is vital to keep inspecting the blades’ performance to determine rounded edges. Chipped teeth indicate you either need a new blade for the saw or it’s time to sharpen.

The appearance of new burn marks is another sign that the blade needs sharpening. These marks are signs of an overworked and ineffective blade. If you will keep working with dull blade it will create more exertion of your saw resulting in higher friction, which causes burn marks.

When cutting material, a dull blade will produce more resistance. You may notice that cutting with the blade is getting harder because it has become dull. A dull blade will require more force to cut and follow low resistance paths. As a result, you make inaccurate cuts when handling different materials. When you cut with a sharp blade, you should experience negligible resistance.

Things To Consider Before Sharpening Circular Saw Blades

Before you start sharpening the blade in your tool, there are some important things that you should know.

You must follow the right procedure to prevent damaging the blade. Equip yourself with the circular saw sharpening tips. It needs consistent practice to make these tips work perfectly. Additionally, don’t settle when it comes to the quality of the blade. Consider investing your money in a quality blade, and you will enjoy the great performance for many years.

Make sure the circular saw blade you use is made of high-quality materials, and it will retain a sharp edge for a long time. A good quality blade reduces the need to sharpen or replace the blade as often.

Step By Step Instructions on How To Sharpen Circular Saw Blades

If you have read above, you must know how to spot a dull circular saw blade, the next step is to understand the sharpening procedure. These steps include the following:

Things You’ll Need

  • Bench Vice. (Or Clamps)
  • Circular Saw Blade
  • Oil (Any wood lubricant or lapping fluid)
  • Sharpening Stick (a File or Sandpaper or a file can work)
  • A small wooden piece


Follow these instructions to get the desired result.

1. Remove The Blade

One thing to notice is that the blades can’t be sharpened when they are still intact with the tool. You must remove the blade from the tool so you can sharpen it. Look for a blade release switch. Most saws have it to help you easily remove the blade. On the other hand, some models require a tool for example a wrench to loosen the bolts and remove. Next, carefully remove the dull saw blade from the circular saw.

Before you start sharpening, clean the circular saw blade first.

Related: How to use circular saw

2. Secure The Blade

Use a clamp or a bench vice, and fix the dull saw blade in place. Use a vice grip and face the tool upwards and teeth towards you. Be careful when tightening the vice. Too much tightening may result in damaging the metal that holds the teeth.

3. Make Marks

Mark the first tooth on the blade with a marker before sharpening begins. Using this technique, you will be able to determine when you’ve covered the entire blade and that one full pass has been completed.

4. Make a Sanding Block

Next, make a sanding block from a small piece of wood no longer than 5 inches long and 3 inches wide. Apply some oil or lubricant to the sandpaper. Lubrication prolongs the life of sandpaper and results in a smoother finish. Place the sandpaper on the surface of the tooth and begin filing back and forth.

5. Refine The Tips

Apply the file to all the tips of every tooth. You don’t need to keep stroking repeatedly. All you have to do is run the file back and forth. This will help you avoid wearing down the tooth. Do this for all the tips of the circular saw blade. Sanding the top of the tooth is not necessary.

File each tooth around five to ten times and continue this process until all the teeth have been sharpened. Start sanding back and forth each tooth of the blade with the sandpaper. Using lapping fluid prolongs the life of the sandpaper/ sharpening stick, as mentioned above.

6. Consider The Bevels

As you will notice, a bevel is there after every two-blade point. Move on to the next step that is finding out the angels to sharpen the blade. Take the blade filer and carry it at about a 20-degree angle towards the bevel.

Use four strokes. If you need to add more strokes, do so until the blades are perfectly sharpened.

All blades have bevel edges. Try skipping one blade and move on to the next bevel edge. Repeat this process until you have gone through the whole blade applying strokes just like you did on the first one.

7. Turn Back the Blade

The same procedure should be repeated on each blade side. Repeat the procedure as described above. Additionally, you must mark the start point to complete this side of the blade.

8. Reinstall the Blade

So, now you have sharpened the blade, release it from the grip and return it to the saw. The blade is sharpened perfectly, and you can start making precise cuts with it.

Check Out: Best mini circular saws in uk

Taking Care of Circular Saw Blades

Maintaining your circular saw blade is important if you wish to extend its blade life expectancy. Here are a few care tips to help you retain the sharpness of the blade.

  1. Keep the blade in a moisture-free place after work. Keep in mind that moisture can erode metal. Hence, remove the blade from the tool to store it in a dry place.
  2. Use the blade for the task it is intended for. Different blades are designed for different purposes. If not used correctly, they can end up damaged.
  3. The blade can become heated if over worked. It is best to take frequent breaks when cutting for a long period of time.
  4. Circular saw blades can acquire grime over time, affecting their performance. Use a solvent and apply it on a soft brush to clean the blade. You can use this cleaning method frequently. It will help the tool keep working properly.

Final Words

Blade sharpness has a huge impact on the final outcome of your woodwork project. When the blade becomes dull after repeated uses, it can cause grain shattering or chipping, affecting the outcome and leading to more material waste.

It is, therefore, crucial to use sharp circular saw blades if you want precision in your work and want to lengthen the blade’s service life. Sharpening the blade requires skills. You may find it a complicated process, but with time you will learn how to do the perfect sharpening.


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