How to Cut Ductwork With Dremel: A Simple Guide For You

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Thinking of installing new ductwork or fixing the old one? You might need to cut the steel surface. And there are a number of tools that would help you with that. 

One of the common tools used to cut ductwork is the Dremel tool. It has multiple functions. And can easily help you cut the metal or still vent pipes.

How to cut ductwork with Dremel?

First, you need to set the metal disk Dremel collet. Then after setting the tool to the perfect speed for cutting, you can start. Make sure the ductwork is firm and that the motor is not burning out. You can simply finish it off by sanding the edges.

There is a way you can use your Dremel tool to cut any duct or vent pipe. If you want an in-depth description of the cutting process, read along. Spare a minute and you’ll be a pro of cutting ductworks.

Why Choose Dremel To Cut Ductwork?

You might want to install a flow-through humidifier in your room. Or a hot air vent for your furnace. Whichever the case, you need to deal with ductwork. 

Now if you want to install a duct, you need to cut and adjust the metal. And you need tools to help you out with that. You can simply use an electric jigsaw or a tin snip to cut the metal.

However, you can also do it with a Dremel tool. It cuts straight through the metal. Not only does it help you with the ductwork, but it also serves other purposes.

But you have more good news! Dremel is so easy to use. You’ll be able to cut steel and tin plates in no time once you learn the basics-

You can sand, sharpen, polish, cut, or even remove grout using this amazing tool. And that’s not the best part, Dremel tools are super easy to maneuver. Which makes cutting as smooth and accurate as possible. 

That’s why most people prefer Dremel tools for households as they are multifunctional.

Before we dive into the steps of cutting ductwork. Let’s take a look at the types of attachments/collets of the Dremel tool. As we’ve mentioned this tool has a lot of functions. And for every function, a Dremel uses a different collet.

However, you don’t need all the collets for cutting ductwork. For this operation, you’ll need the sanding bit and the metal disk bit. These two collets will help you to get your ductwork job done. This tool will also work in case you’re using a duct board.

These attachments are available in most hardware stores. But we’ve curated a list of the products for your convenience-

You’ll also need ear and eye protection while using the Dremel. There is a possibility of producing sparks. Once you’ve gathered the tool, let’s dive into the steps of cutting ductwork-

Step 1: Set Up The Required Attachment

The first step for you is to attach the right collet to the Dremel. To cut the ductwork, you need to use the metal disk collet. There might be various shapes and sizes. You have to choose the right one. Choosing also depends on the material and its thickness.

Make sure the collet attaches to the Dremel firmly. Otherwise, there’s a chance of severe injury when the collet speeds up.

Step 2: Find Out The Cutting Speed

As Dremel rotates the collet like a mini drilling machine, speed is important. If it’s too fast or too slow, it might damage the metal and the Dremel itself. Usually, for metals, the speed level could be set anywhere between 4-8. You can turn the switch to the required speed.

Now, you might have to refer to the manual while cutting. Because the speed levels of materials are different. 

However, it’s time to stop when the motor of Dremel makes a noise. Or if you have to put in a lot of effort while maneuvering the disk along the surface. You’ll have to change the speed settings again.

Step 3: Start Cutting The Metal Ducts

Once your speed level is okay, it’s time to start cutting the metal ducts. You’ll have to make sure the pipe is steady. You can also use a clamp or a vise to keep the ducts firm.

After that, you start pressing the metal disk lightly to the metal surface. You must wear eye and ear protection because there will be sparks. If the metal starts cutting, slightly increase the pressure every few seconds. 

You might need a steady hand to maneuver the required cut in your duct pipe. To do that, you’ll need a bit more practice.

Step 4: Sand The Edges

The best part about using a Dremel is that you can sand the edges after cutting. But for that, you need to use a different collet. The sanding bit will add the finishing touches to your cut. You can also insulate the ductwork.

Now you know how to use a Dremel to cut the ductwork.


Question: What are the different Dremel attachments for?
Answer: There are many kinds of attachments to the Dremel tool.  All of them have different functions. The kinds are- Sanding Bits, Cutting Bits, Etching, and Engraving Bits. Some also include- Drilling Bits, Grinding, and Sharpening Bits.

Question: Can I cut wood with Dremel?
Answer: Yes you can! Dremel is a rotating tool to help cut or engrave any material. This includes metals, plastic, and wood. However, you might not want to cut a thick metal with Dremel. You’ll require a different tool for that.

Question: What can you do with a Dremel tool?
Answer: Dremel tools are multifunctional. You can use them for sanding, drilling, and even cutting metal. You can use this tool for engraving. Dremel is literally lifesavers. 


By now, we hope you know how to cut ductwork with Dremel. This tool will make your work in the furnace super easy. All you need is to remember to use the right amount of speed and force.

Till then, happy drilling!

Scott Kelly