How To Cut Plastic With A Dremel or Rotary Tool – A Simple Guide


Dremel is a good tool for cutting many materials, and plastic is one of them. A Dremel will cut through most plastic materials quickly and is great for doing detailed cuts. Most Dremel models will have a motor that is powerful enough to cut through the plastic.

To cut plastic with a Dremel we generally use the Plastic Cutting Disc #SC476, the Reinforced Cutting Disc #SC456, or the smaller more fragile cutting discs #409 or #420. Secure the cutting bit in the Dremel, secure the plastic object you are cutting, put in the power cord, start the Dremel, slowly lead the cutting bit onto the plastic and start cutting.

That was the short version on how to cut plastic with a Dremel. I will get more into detail on why we use the different cutting discs, how to be safe when cutting, and also a step-by-step guide to cutting plastic with a Dremel.


Safety and Safety Gear For Cutting Plastic With A Dremel

Even though safety is not the most fun part. It is important, and we have to go through it. So let’s go through the safety before we start the cutting.

In general, cutting plastic with a Dremel is a fairly safe activity. The Dremel has no problem cutting through most plastics, you do not have to use much force, and it is easy to maintain control over your tool.

Always keep a steady hand while cutting with the Dremel, the material can suddenly lead the cutting direction and the tool might do a little “jump” where you have little control. But as long as you keep a steady hand and pay attention to the cut you should be fine.

Safety Gear When Cutting Plastic With A Dremel

Safety Gear When Using Dremel
Safety Gear When Using Dremel

Protective Glasses – Always use protective glasses when using the Dremel. Cutting discs can break, bits can come loose and shards of plastic can come flying at you. Always wear safety glasses.

Gloves – Gloves are optional when cutting with a Dremel. Gloves protect you from heat, and flying particles. But introduces the risk of the gloves getting caught up in the tool when it is running. I choose to use gloves when cutting, decide what works for you.

Dust Mask – A dust mask is very important to use when cutting with the Dremel. At a minimum, use a simple disposable dust mask and do your cutting in a well-ventilated area. Cutting can produce small plastic dust particles, and we do not want them in our lungs.


Cutting Wheels For Cutting Plastic With A Dremel

There are four types of cutting wheels, discs, and bits I recommend for cutting plastic with the Dremel.

Dremel Cutting Discs For Plastic
Dremel Cutting Discs For Plastic

Plastic Cutting Wheel #SC476

Uses #SC402 Mandrel

The plastic cutting wheel is a reinforced cutting wheel that is designed specifically to cut plastic. It will make clean cuts and produces smooth edges that need little finishing work after the cut is done. This cutting disc is most of the time not included in the default bit set, accessory pack when you buy the tool.

If you do not have this disc and don’t want to buy it. You can use the cutting discs below, they are usually included when you buy the Dremel.

Reinforced Cutting Wheel #SC456

Uses #SC402 Mandrel

The normal reinforced cutting wheel is mainly designed for cutting metal. But it will cut plastic just as well. I have used both the plastic cutting wheel and the metal cutting wheel for cutting plastic, and I can hardly tell the difference.

The Smaller Cutting Wheels #409 and #420

Uses #402 Mandrel

The smaller cutting wheels are also great for cutting plastic. They are thinner, which makes them cut through the plastic quicker. This also makes them more fragile and they will also wear out quicker.

If the discs are put under too much pressure (especially sideways) while cutting, they have a tendency to break while running. But if you have proper safety gear, it causes little danger.

Spiral Multipurpose Cutting Bit #561

Used with #565 Cutting Kit

The Spiral multipurpose cutting bit is good for doing detailed plunge cuts in plastic. This guide will focus on using the cutting discs to cut plastic. But if you need to do detailed cutting in plastic, like circles in the middle of a plastic sheet, or other shapes. This bit and attachment is the tool to use.


How To cut plastic with A Dremel – Step By Step

1. Choose Cutting Bit

Decide which cutting bit you want to use for cutting the Plastic based on the bit guide above. I recommend using the smaller cutting wheels for thin plastics, and the thicker reinforced cutting wheels for more solid plastic.

2. Secure The Bit In The Dremel

Bit Secured In Chuck

Put the bit inside the chuck, then tighten the chuck nut while holding down the spindle lock button.

3. Secure The Object To Be Cut

Secure Plastic With Vise
Secure WIth Clamps

We need to secure the plastic object in some way. Sometimes a good grip with your hand will do the job. But if you have the opportunity, I would recommend securing the object in a vise before starting to cut.

4. Mark Where You Want To Cut

Marking The Cut

Marking the cutting area will help you make a better cut. Use a marker to mark the area and guide you through the cut

5. Plug In The Power

The object is now secured, you marked your cut, and the bit is fastened. Put the power cord in the socket and get ready to start cutting.

6. Set The Dremel To 12000 RPMs

It is important to use low RPMs when cutting plastic with a Dremel. The plastic can melt if the heat from the friction gets too high. Start the Dremel at 10000 – 15000 RPMs and try cutting with a low rpm first. If that works fine you can try higher RPMs and find the limit for the plastic you are cutting. Different plastics will handle the heat in different ways.

7. Turn On The Dremel

Let’s get cutting. Keep a steady hand and turn on the Dremel.

8. Slowly Start Cutting

Cutting Plastic With A Dremel
Cutting The Plastic

Now you can slowly lead the running Dremel bit onto the plastic. Keep a steady hand and get a feel for how the tool cuts and works. Let the tool do the cutting and do not force the cut. The most important part now is that you get to practice and use the tool, use slow movements and try to get straight and clean cuts.

9. Adjust RPMs

Now, some plastics can handle quicker RPMs. And quicker RPMs also mean straighter and smoother cuts. Try cutting with different RPMs and see what you like cutting with the most. If the plastic starts to melt, use a lower RPM.

10. Cut Straight Lines

Straight Cut with Dremel
Example For Cutting A Straight Line

There is no magic to cutting straight lines with a Dremel except keeping a steady hand. You can however clamp a straight thin metal piece to the plastic and use it as a guide. You can also make small steering cut into the plastic before cutting all the way through.

11. Doing Plunge Cuts

Plunge Cut With Dremel
Doing A Plunge Cut

Plunge cuts are when you use the bit to cut straight into the material like the picture above. You can do plunge cuts with cutting discs. Bit it can be hard to stay detailed when doing it. For more detailed plunge cuts, use the smaller cutting wheels.

For doing precise and detailed plunge cuts I recommend using the #565 Multi-Purpose Cutting Kit.

12. Finishing Touches

Sanding Edges With Dremel
Sanding The Edges

When you are finished with cutting. The edges might be rough and plastic debris will be hanging around the edges of the cut. Use a Dremel drum sander bit or grinding stone to remove the rough edges.


Questions About Cutting Plastic With The Dremel

What Is The Best Dremel For Cutting Plastic

Most of the Dremel models will be able to handle cutting plastic. Some of the weaker ones like the Dremel Stylo+ might have some trouble with thick plastics. The best all-around Dremel for the best price is the Dremel 4000 with the Flex Shaft Attachment.

Can You Cut Plexiglass With A Dremel

You can cut plastic with a Dremel, but it is not recommended. It is better to use saws with serrated cutting edge, a jigsaw is a good example. The cutting discs for the Dremel have a tendency to clog up and melt the material when cutting plexiglass. The best Dremel attachment for cutting plexiglass is the Dremel mini saw 670 with a serrated cutting edge.

But a jigsaw or a table saw is way more convenient for cutting plexiglass than the Dremel. But the Dremel works fine for cutting very thin pieces of plexiglass.

What If The Plastic Melts While Cutting?

If the plastic is melting while you are cutting it with the Dremel, there is too much friction between the cutting bit and the plastic. Try using a lower RPM to decrease the friction between the Dremel bit and the plastic. The thinner cutting bits are also better at cutting plastics that melt quickly when cut.

When the cutting bit is thinner, it causes less friction and has to remove less material. But the thinner cutting bits are also more fragile and prone to breaking.

The thickness of the plastic will also have an impact on whether it will melt or not while being cut. The thicker the piece of plastic is, the more time you have to spend cutting in a single area and heat will build up and eventually melt the plastic. But it does of course depend on the properties of the plastic.

What Is The Thickest Piece Of Plastic You Can Cut With A Dremel?

The absolute thickest solid plastic piece you can cut with a Dremel will be about 1.1-inch (2.8 cm) thick. The largest cutting wheels for Dremel have a radius of 3/4-inches (1.9 cm). But the bit that the disc is secured to limits the cutting radius to about 0.6-inches (1.5cm). So to cut a piece of plastic that is 1.1 inches (2.8cm) thick you have to cut it from both sides.



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