How to sharpen a hole saw?

A hole saw is a circular saw blade with teeth on the edge designed to cut through a hole in a piece of material. 

These circular blades powered as a drill attachment are used to cut medium to large holes in wood, plastic, and metal.

Hole saws can become dull over time, which will make them frustrating to use as the bits become more difficult to operate with as the sharp edge wears down.

Blunt blades can also result in damage to your projects or the material you are cutting by leaving behind a ruff-looking cut or burst splinters and chips from wooden surfaces.

Is this possible, to sharpen a hole saw?

A hole saw comes in handy when you need to make a large but perfectly shaped hole in a piece of building material. 

Usually, hole saws are used on wood, plastic, or metal but can surprisingly be used to cut holes in glass with the right tip material.

Unfortunately, there comes a time when even a hole saw will become dull and need to be sharpened especially if used on stainless steel, or accidentally hits a nail, concrete, or fiber cement board during use. 

Luckily, sharpening is possible when a hole saw is blunt to save money on a new one.

There are a few different ways that you can do this. The best method chosen depends on the type of material being cut and how often you use your hole saw.

Signs that your hole saw needs sharpening

If you have good experience with hole saws already and how sharp one should be, you can probably tell just by looking at the teeth to find out whether the drill bit needs sharpening.

Otherwise, I lightly tap my finger on the edge of the blade this gives me an indication of the current condition of the drill bits’ sharpness.

However, if you’re not sure, there are a few other signs that can help you decide on when to do maintenance or get a new hole saw.

1. Bluntness

When a hole saw becomes blunt, others will be noticeably lost smoothness and the ability to cut as quickly.

It becomes more challenging to cut through the material, and you may end up damaging your material in the process.

2. Round teeth

Hole saws are designed with sharp teeth on their edges to cut effectively through even thick materials like wood.

If you find that the edges of your hole saw are rounded, now is time to sharpen the teeth [1].

3.. More pressure applied when drilling

When a hole saw is sharp, you should be able to drill through your work materials with little effort.

However, if you need to apply more pressure than usual or if you are having difficulty drilling holes altogether, chances are your drill bits need sharpening.

Make sure that you are using a powerful cordless drill that is up for the task.

Different ways to sharpen your hole saw 

Sharpening a hole saw depends on the type of material you’re cutting, how often you use your tool and what method works best for you. The difficulty level of sharpening a hole saw also varies based on these factors.

Below are the three best ways that you can use to sharpen your hole saw. Choose the one that works best for you to get you back to work.

1. Using a hand file

A hand file is one of the most used methods for sharpening hole saws because they are affordable, easily found, and easy to use for basic tasks.

Different types of files work with wood, plastic, or metal, meaning that fine files can sharpen metal blades to an extent, but not as much as a sharpening stone used in other methods of sharpening technology.

Files are ideal for novice users because the hand tool is simple and has an easy operating process for almost anyone. 

A hand file doesn’t require any special skills or safety guidance. 

As a note: I always make sure to have a range of files ready to go in my toolkit for different jobs and deburring sharp metal edges.

Here are the steps to sharpening a hole saw by hand:

1. Clamp your hole saw onto a bench vise or securely fastened to a workbench with a clamp.
2. Use a hand file when sharpening hole saw teeth on the edge of the hole saw. Be sure to hold the file at the right angle and use light pressure as you sharpen the hole saw tooth one by one.
3. Focus on each tooth individually while you sharpen them, paying attention to the edges that have become rounded, keep stroking until you hear a higher pitch consistent sound that lets you know the edge is sharp. 
4. Check the sharpness of your hole saw by cutting through some material. If the blade is still not cutting effectively, continue sharpening again, or try a different method.
5. If you are unable to restore the original angle and sharpness consider getting a new and higher quality hole saw kit, that keeps a sharp edge better.

2. Using a Dremel

This method is more popular with metal and plastic blades. And also suitable for frequent use, but requires you to have some practice to do this method well.

A Dremel is a handheld rotary tool that many people like me and other DIYers and builders use to cut, sharpen, grind, and polish a range of materials and tools.

Follow the steps below:

1.  Clamp your hole saw onto a bench vise or fasten the chuck securely to a workbench.
2. Use the Dremel tool to sharpen the teeth on your hole saw. Here’s how you can change your Dremel rotary bit with a sharpening disc. When doing so, hold the Dremel horizontally and make sure that your teeth are aligned at a 90-degree angle. 
3. To avoid sparks from flying from the Dremel, move the tool back and forward at a slow pace as you sharpen. This also helps to avoid overheating which can damage your teeth, and cause them to blunt faster in the future.
4. Unclamp your hole saw once you’re done sharpening it.

3. Using a universal sharpener

This method can be used on wood, metal, or plastic cutting blades.

One of the quickest and easiest ways to sharpen a blunt hole saw we found is with a universal sharpener.

Thanks to the rotating sharpening head that works on both sides of a drill bit.

However, a new tool like this can be difficult to get the hang of at first. 

Finding a new hole saw kit is often easier and more affordable, and time-saving for most people who dont need to regularly sharpen these types of bits.

Unless you have to sharpen hole saws frequently buying a new higher quality kit is normally a better idea.

Once you get the hang of using a universal sharpener many DIYers say they find sharpening easy on a blunt hole saw bit that can now be recycled and reused.

Here are the steps to follow:

1. Clamp your hole saw onto the universal sharpener.
2. Use the universal sharpener to sharpen the teeth on your hole saw. The sharpener is made up of two parts, and you will need to attach the part that fits your hole saw and align the position with the part for grinding and sharpening a new cut edge.
3. Once you’re done sharpening, unclamp the tool from your workbench and store your sharpening tool away safely.

What tools cannot sharpen hole saw bits?

While there are many ways to sharpen a hole saw, there are also a few tools that you cannot use, as it’s a bit dangerous and harder to do.

These include:

1. Bench grinder

A bench grinder is used to grind down metal materials.

Although a table grinder is not suitable for sharpening hole saw bits because the grinding wheels are too large and harsh and can cause further damage to the teeth of your hole saw.

However, a slow-speed grinder, a thin grinding disk, and the hands of a surgeon may get the job done.

2. Angle grinder

An angle grinder is not ideal for sharpening hole saws either because the blade is too powerful and can easily damage the teeth from over-cutting and grinding.

You would have to secure your grinder in place and wear a full face shield, in case the blade shatters that is why we do not recommend using an angle grinder to sharpen drill bits.

You would need the hand stability of a surgeon to successfully pull this off and to have enough detailed control over your angle grinder.

Safety tips for sharpening a hole saw

When sharpening a hole saw, be sure to take the necessary safety precautions:

• Wear protective gear – Use gloves and tight sealing eye goggles to protect your eyes and hands from getting cut or scraped by the file or power tool. If you’re using a Dremel tool, also wear ear protection.
• Secure your work area – Make sure that the surface you’re working on is secure and won’t move around while you’re sharpening your hole saw. This will help to prevent accidents from happening.
• Be patient – Sharpen your hole saw slowly and carefully to avoid damaging the edges of your tool by creating uneven-sized teeth.

Maintenance tips for using a hole saw 

• Since you don’t want to sharpen your hole saw often, take good care of it. For example, use a hole saw cutting fluid when drilling holes in metal materials. This will help prevent your bit from overheating and burning out or breaking down prematurely due to wear and tear.
• Always clean your hole saw after every use. If there’s any debris left on it, wipe them off with a damp cloth or brush before storing the tool away for next time. You can also store them in a nice rugged plastic container to prevent damage from rust or corrosion caused by moisture exposure over time.
• Have a prized hole saw kit, and use your older hole saws on materials like plasterboard.
• Never use a hole saw not designed for the material you are cutting or you can blunt your saw blade quickly. For example, wood-only hole saws should never be used to cut metal.

Final thoughts

Hole saws come in handy when installing pipes, wires, lights, and other hardware in walls or ceilings without damaging anything else around them. However, a blunt hole saw is less effective and harder to use.

If you want your tool to stay sharp for as long as possible, you must take good care of your hole saw by following our tips and maintenance steps.

However, if your hole saw needs to be sharpened more often than usual or the teeth are starting to rust or corrode, it may be time to get a brand new hole saw tool kit.

Save yourself the trouble of having to constantly sharpen your hole saw by investing in a new higher-quality kit.

I can help you find exactly what drill kits to use here.