Acrylic is a durable, clear form of plastic, and as such has different properties than metal, wood or other materials. You can certainly use your CNC router to cut acrylic sheets, but the following tips will help you avoid irregularities or difficulties and help you maintain a smooth cut.
Use A Specialized Bit
Be sure to use a bit specifically designed for cutting acrylic, as standard wood or metal bits won’t do as good a job with chip removal and can cause a rougher cut as a result. These bits can usually be found at your local hardware store.
Select A Larger Bit Size
When cutting acrylic, a larger bit size tends to do a better job removing the chips than a smaller one. Try to use the largest bit size possible that is still conducive to your project. As a starting point, a 0.25” bit seems to be workable for most acrylic sheets.
Secure The Acrylic
Acrylic tends to vibrate, so make sure it’s held down securely when you begin cutting. Too much movement and shaking will make your cut rough and uneven.
Cut At A Steady Rate
One of the most common problems with using a CNC router to cut acrylic is that when the acrylic heats up due to the friction, the edges of the cut tend to melt and remold, effectively bonding the acrylic back to itself after you cut through it. You can minimize this issue by increasing the IPM so that the bit and the plastic are not in contact any longer than necessary. Don’t be reckless, but cut through the acrylic as quickly and steadily as you can while maintaining control.
Keep The Acrylic Cool
If you are still having problems with the acrylic re-bonding due to the heat, you may have better luck if you put the acrylic in a freezer for an hour or so before cutting it, so the starting temperature is lower. Also, feel free to use a cool mister on the plastic and the blade from time to time to moderate the temperature.
CAMaster is committed to helping you get the best use of your router. By following these tips for using your CNC router to cut acrylic, you’ll have better results and a nice smooth cut. Contact us today to discuss your router needs.