How to Sharpen a Large Circular Saw Blade by Hand

If you are using a multi-tool to cut wood, metal or be it any other type of material. The tool is only good if it is sharp enough to cut through any thickness of the material you intend to use. A circular saw is a common tool that a handyman needs because it has several uses.

Brief History of the Handy Tool-Saw

The first-hand saws were made around the 4th century. Dozens of hand saws from this era have been found. These highly ingenious saws were used like sharpening files for making accessories, not cutting wood. Artifacts such as paintings showed saws used in Egyptian times. These saws were made of copper and were depicted as large blades without handles. Egyptians used open pull saws from copper that were retrieved as early as the Early Dynastic Period (3,100-2686 BC). These saws were initially made of hardened copper with teeth so they could cut with pulling and pushing motions. As saws evolved, the teeth were scooped to cut and set only on the pull stroke, rather than the modern alternating setting method, with the teeth protruding only on one side. 

It is believed that the Romans came up with the idea of ​​using a wooden frame to hold the saw blade better to control the depth and direction of the cut. Evidence of saws found in Japan suggests that an early version of the hacksaw was developed in the 15th century. Buddhism was taught in Japan in the 6th century. It had a significant influence on woodworking tools. Until then, crosscut saws were the only saws for woodworking in Japan. The rip saw was introduced in the middle of the Muromachi Period. 

Different attributes of saw origin came into existence. One example is that Lu Ban, a Chinese architect or master carpenter, invented the first saw, according to Chinese legend. However, in archeological findings, saws were used as early as prehistory and most probably became a woodworking tool from Neolithic stone. Further, despite the different early designs, saws didn’t become popular until 1650 with the development of rolled steel. By the 1800s, almost every household had some form of saw, but most were intended only for cutting wood. 

After use of the power saw, the blade tends to get blunt. There are few options when your blade is blunt, and you can either buy a new one or the other economical means to sharpen the blade so that it can perform effectively. There are many ways to sharpen the blunt blade, here you will get to know a simple step by step method of sharpening your blade by hand.

Safety Tips You Should Follow

Before you begin any sharpening operations, these are safety tips that you should follow:

  • Put on eye goggles to protect your eyes.
  • Put on thick gloves to protect your hands
  • Wear a dust mask and ear protection.
  • Stand on the side to avoid any kickbacks.

Remove the Large Circular Blade

Before you start to remove the blade from the circular saw, make sure that the saw is not connected to any power source. If so, switch off the power and remove the power saw’s plug from the socket. Most circular blades have an arbor lock for safety. Engage the arbor lock so that it can free the blade. Take a wrench, most preferably the one that came with the circular saw blade.

Place the wrench on the nut and rotate it in the same direction that the blade turns to, for most saw this direction will be anticlockwise. After removing the bolt, place it aside and carefully remove the blade from the saw by sliding it gently off.  You can also consider a heavy duty miter saw blade replacement as well.

1. Sharpening by the use of a file

This is the oldest method of sharpening a saw blade. The work may be physically tasking, but it is technically simpler than any other method. The process involves securing the blade on a base and scrubbing of the face side of the blade so that it can be sharp.

Securing the blade

To be able to secure the blade for the sharpening process to happen, you will need to have two pieces of wood and a clump. On your work table place one piece of wood on it. Take the circular saw blade and place on top of it, take the other place of wood and place it on top of the blade. Make sure not more than a third of the blade teeth stick out in between the two teeth. Clamp them together firmly.

Filing the blade

Mark the starting point of the blade using chalk or a washable marker so that you know where you will end up. Place the file at an angle on the cutting surface of the blade. While filing, make sure you don’t pull back and forth, this procedure will make your file dull in no time. Alternative make forward gentle strokes for about five seconds. Move to another section when you are done.

When you are done filling the exposed surface of the blade, unclamp the set upturn the blade to expose the other surface. Repeat the process until the whole blade is sharpened. Turn the blade on the other side and use your file to sharpen it also. To make your blades sharper, you can repeat this procedure about three times for effective cutting.

2. Using a Dremel to sharpen a circular saw

Take a cylinder wood piece of the same diameter as the hole of the saw blade. Cut wood pieces into square pieces and attach to the cylinder piece. Secure both the cylinder and square pieces tightly. Place your blade on the cylinder and make sure that the teeth of the blade are visible from the wood pieces so as to be sharpened.

Take the Dremel and place it at a 90-degree angle of the saw blade on the left side. Before securing the Dremel make sure that it is in contact with the teeth of the blade. If not make adjustments.  Mark the starting point on the blade to prevent double sharpening. Rotate the saw blade so that all the teeth are sharpened for about two seconds. Repeat the process on the right surface side of the blade.


After you are done sharpening your blade, you will need to attach it back to the saw. First, clean the saw to remove any metallic residue on the surface of the blade. Clean the blade guard by wiping it using a piece of cloth. Place it back on the saw and take the bolt and by use of the wrench tighten it to secure the blade. Switch on the saw to test the sharpness of the blade by cutting through a piece of wood.

Frequently Asked Questions

Q:  how long does it take to sharpen the blade?

A:  it will take you an average of five minutes to sharpen your blade using a Dremel tool. It will take longer if you use a file to sharpen the blade.

Q:  how long does the sharpness last after sharpening?

A:  it will depend on the frequency of the use of your blade. If you use the blade too much, you will notice the blade getting dull by it getting slow in cutting or straining in its operation.


Both of the techniques of sharpening will get your blade sharp for use. To be able to choose from either of them, make sure you know the available tools you have in your workshop. A simple method of sharpening is by use of the file. The Dremel method is fast but do not use this method if you are not able to secure both the Dremel and the blade.

You can be able to do either method by having an oscillating multi-tool. An oscillating multi-tool uses side to side movement to perform its operations. With such tool on your hand, it can be used to sharpen your blade. While sharpening a blade safety should be your top priority.