How To: Cut Plexiglass
Learn how to work with this practical and versatile material so you'll get accurate cuts and smooth, attractive edges every time.
In a range of applications, from picture frames to tabletops, plexiglass (also known as acrylic) serves as a cost-effective, shatterproof substitute for glass. In fact, due to its light weight and durability, many do-it-yourselfers prefer plexiglass, not least because it can be cut and shaped with common workshop tools.
Versatile and tough though it may be, plexiglass isn’t perfect. For one thing, it scratches easily. That’s why sheets of the material come covered in a thin layer of protective film. The other downside? Homeowners who don’t know how to cut plexiglass can be intimidated by the material at first—but we’re here to help!
When cutting plexiglass, leave the film in place as long as possible to avoid marring the surface. Second, bear in mind that even if you’re careful, it can be difficult to cut plexiglass without leaving a rough, irregular edge. If your project requires a clean edge, expect to devote energy to smoothing the finish. Simply cutting plexiglass to size is easy by comparison.
Continue reading for details on how to cut plexiglass—the right way.
How to Cut a Thin Sheet of Plexiglass (with a Utility Knife, Box Cutter, or Glass Cutter)
For a thin sheet of plexiglass—that is, material up to about 3/16-inch thick—use a scoring method not dissimilar from a technique used to cut actual glass.
- Lay the sheet on a flat surface and, using a yardstick and a permanent marker (or a grease marker), measure and draw the line you wish to cut.
Next, hold the yardstick to the marked line, and run the dull side of a utility knife or specialty plexiglass cutting tool along the yardstick to score the sheet.
- Score again and again, as many as 10 or 12 times, until you have made a deep groove in the plexiglass.
- Flip over the plexiglass, and score the opposite side in the same manner.
- To finish, hold the scribed line to the edge of your work surface, and secure the plexiglass in place with a clamp. Then, with sharp downward pressure, snap off the portion of the plexiglass that extends beyond the work surface.
RELATED: How to Clean Plexiglass
How to Cut a Thick Sheet of Plexiglass (with a Circular Saw, Saber Saw, Table Saw, or Jigsaw)
No matter which type of saw you choose for the task, it’s critically important to use the right blade. There are special blades designed expressly for acrylic, but any metal-cutting blade with carbide tips can do the trick. Before committing to one blade or another, double-check that its teeth are evenly spaced, with no rake, and of uniform height and shape.
After readying your tool, measure and mark the plexiglass, then cut as you would any other material, clamping if appropriate. One note of caution: If the blade overheats, the material may chip or crack. Proceed accordingly, water-cooling the blade or pausing your work for a few minutes as needed.
How to Polish and Buff Cut Edges
Whichever cutting method you choose, you may find that the cut plexiglass edge doesn’t look terribly attractive. If the cut edge would be visible in your application, take the extra time to sand and buff out the imperfections. Note: You can use a handheld power sander, but manual wet-sanding typically achieves the best results.
- Start the process with 120- or 180-grit waterproof sandpaper, in combination with a wood or rubber sanding block.
- As the plexiglass becomes smoother, transition to successively finer grits. Finish by sanding with 600-grit sandpaper.
- Once you are satisfied with the appearance of the edge, move on to buffing. Outfit your electric drill with a buffing pad and, after applying a polishing compound formulated for plastic, bring the plexiglass edge to a perfect polish.
Tips to Avoid Cracking or Breaking Plexiglass as You Cut
Though plexiglass is a durable material, it’s not unbreakable. Keep the following tips in mind when learning how to cut plexiglass to prevent irreversible damages.
- Keep the plastic film on. As mentioned above, plexiglass usually comes with a thin layer of plastic film intended to prevent scratches as the material travels from manufacturer to retailer to your workshop. Leaving that film on as you measure, mark, and cut will prevent scratches from your tools and work surfaces.
- Score deep. When using a knife such as a box cutter to cut plexiglass, be sure to score a straight, deep line before attempting to break the material at the mark.
- Use the right blade. Whether using a hand tool or a power saw to cut plexiglass, it’s important to use a sharp blade. A dull blade will fight against the material, potentially causing cracks and breaks—not to mention an overly rough cut edge.
- Keep the blade cool. As mentioned earlier, an overheated blade on a power saw can also cause plexiglass to crack and break during the cutting process. Leaving the thin plastic film on the surface acts as a lubricant to an extent, but if your blade starts to overheat, pause and turn off the saw to let it cool. You can also add a small amount of soapy water to the plexiglass surface for additional lubrication while cutting.
RELATED: How to Cut Plastic
Final Thoughts on How to Cut Plexiglass
Every building material comes with a set of quirks and nuances that you can master with practice. Fortunately, it doesn’t take long for do-it-yourselfers with woodworking experience to learn how to cut plexiglass.
Although for the time being, you may only need to cut a piece of acrylic down to size, learning to work with this versatile, transparent material opens up a new universe of DIY possibilities that you can explore in myriad projects for years to come.