With uses from lenses for glasses to windows and picture frames to tables, plexiglass is an extremely versatile material that we find everywhere around us today.
But knowing how to cut it can be difficult. With the correct tools and set up, you can get clean, professional cuts for a product that you and your customers will love.
Although thin and small pieces of plexiglass can be cut with a specially designed plexiglass knife, we want to find out how to use a circular saw to get the best cuts.
How to Cut Plexiglass With a Circular Saw?
Before you can cut your plexiglass, you will need a few things for a safe workshop and a professional finish. Take time to prepare beforehand so that you will not have to come back to this job later, possibly leading to poor cutting and a sloppy finish.
You will need:
- A plexiglass sheet (a sheet is defined as anything that is half an inch or more in-depth)
- Your circular saw
- Clamps, to hold the plexiglass sheet in place
- Appropriate safety equipment, including a face shield and ear protectors
- A sawhorse (or any other workbench)
- A marker
- Coolant for the blade, made from detergent and water
- Tape that can be used to stop splintering
- A straight piece of wood that you can use as a guide block
Taking time to prepare before carrying out a project will save you time in the long run!
Setting Up the Circular Saw
When readying your saw for working with plexiglass, you need to focus on three areas: the size and type of the saw, the feeding rate, and the blade depth.
An ideal saw type for working with plexiglass is a carbide-tipped bladed one with a high number of teeth. Although you don’t need a blade with over 100 teeth, a high number of blades will reduce the chances of drag and chipping.
If you have too few teeth, the blade will hack through the material and cause more damage than it will actually cut. Professional recommendations tend towards a 10-inch blade with around 80 teeth. Any specifically designed plexiglass blade should work well, however.
The feeding rate should be kept low to avoid damage from overheating the saw and damaging the thermoplastic material. Keep this close to 3 inches per second. This will give you a smooth cutting experience that does not hack at the material.
The blade depth should be set as half an inch below the sheet. Moving from this measurement too much can cause damage to the sheet and render it useless to you, wasting materials and time.
If you cut too deep, you will have more of the saw touching the sheet than you need. This can cause splintering and chipping where the most extreme parts of the blade touch the sheet. Chipping can lead to cracking and a cracked piece of plexiglass is a useless piece of plexiglass.
If you cut too shallow, you could be left with an incomplete cut that needs a repeat treatment. Having to repeat any section of a cut increases the chances of cuts going off-center and potential chipping due to the material being weakened. Take your time and cut the plexiglass at an appropriate depth.
When your saw is set up correctly, you can begin to make your cut.
Taking Care of Safety First
Plexiglass can be a particularly difficult material to work with for two reasons – it splinters and it is very loud when cut. For these two reasons, you must take time to put the proper safety equipment on.
Absolutely necessary are hearing protection and a face shield. You may also want to wear gloves and other protective clothing.
You need hearing protection due to the sound of cutting plexiglass – it is deafening! Taking care of your ears is important, so a good pair of ear defenders are a must. You can find affordable pairs in any good shop which has a woodworking or home improvement section.
When you cut plexiglass (especially if you make a mistake and cut it too fast), there is a chance that it will splinter and the pieces will fly towards you. Wearing a face shield will protect your eyes. Continuing in this line of work without your eyes would be practically impossible, so think carefully before you decide not to wear one.
As the splinters may be launched towards your arms and chest, you may also want to wear heavy, long-sleeved clothing that will protect your skin. It is unlikely that you would be injured by a shard, but splinters can lead to infections if not noticed or not treated properly.
When you have the appropriate safety measures, you can begin positioning your plexiglass sheet.
Setting Up the Plexiglass
Before even moving your plexiglass, you should know that you should not remove the protective film that covers it. I repeat, do not remove it!
The film is there to protect the easily scratched surface of the sheet and should not be removed until after the cutting is finished. As the product is so vulnerable to scratching, you should leave the film on to avoid accidental damage from other tools.
To set up your plexiglass, place it on top of your sawhorse (or another workbench) and have the section you want to be removed from the sheet hanging off the support. Ideally, this should be at a 90-degree angle for ease of cutting.
Secure the sheet with clamps and check for stability. If the sheet falls while you are cutting it, it will almost certainly ruin the job and you will have a wasted sheet of plexiglass due to an easily avoidable problem.
After setting up the plexiglass correctly, you have to mark the line that you want to cut.
Marking the Cut
Take a marker pen and draw a straight line across the plexiglass. For a professional finish, you should be using a ruler and not a free draw!
At this point, you may want to take the tape and make a line across your plexiglass. This will help you stop splinters during the cut and give you a cleaner finish (and less to clean up afterward!)
When you have taped the plexiglass, take the marker and mark a straight line with a ruler. This will help you see the line for your cut clearly even if you already drew a line under the tape.
Improving Your Accuracy
Using a guide block will give you a hard boundary to guide your circular saw through the cut. This will help keep a blade on a clean line throughout the cut, saving you from relying on your eyesight and potentially running the job.
It will also help you maintain a steady speed when cutting as you will only have to focus on how fast the blade is moving. Maintaining a steady and slow speed is necessary for professional plexiglass finished products.
Measure the foot of your circular saw (this is the metal part that sits below the blade). Place the guide block so that the blade lines up with the marker line when the foot sits against it and clamp it to your sheet so that it is secure.
When the line is marked clearly, you can begin to prepare your circular saw.
Treating Your Circular Saw
Before making the initial cut, you need to understand how to prepare your saw. Unlike wood, plexiglass will not withstand the heat and speed of a circular saw (or most other power tools). You need to approach it in a different way.
If you spin your saw at full speed, the teeth will rip through plexiglass and cause severe splintering and cracking. As the saw is used, it will heat up. The heat can lead to the sheet melting and cause irreparable damage.
To avoid heat melting your project, apply a coolant to the saw. When cutting, work through small sections at a time and take regular breaks. This will give the blade enough time to stay cool.
If you do not have access to a coolant, water treating the blade also works when combined with regular breaks. This can be done with a spray bottle – using a water bath is not advised with electric equipment due to the risk of serious injury and death.
When you have safely set up your circular saw and a ready to get started, you can begin the cut.
Beginning the Cut
Taking your circular saw after you have applied the circular saw, set the blade so that it lines up with your marker line. Double-check that the guide block fits well with the line and the saw.
Keep your blade to a low speed. Ideally, you want a blade that spins at 3450 RPM – this is the advised rate for dealing with plexiglass. Even if your blade works exactly at this rate, however, you still need to keep the blade cool and take regular breaks.
When the blade is prepared properly and in the correct position, begin the cut with a smooth and steady motion. Keeping the cut slow will reduce the chances of chipping and cracking.
Effective Aftercare for Plexiglass
When taking a circular saw to plexiglass, you have to prepare to properly care for the materials afterward. Even the best saw with the best cutting technique will lead to a rough edge and a small amount of splintering.
Remove the tape that you have used to catch splinters. Take fine sandpaper to the edge of the cut to smooth it over and give a professional finish to the sheet.
When you have treated the edges and removed the tape, you can also remove the film which has been protecting your sheet from scratches. This should be the last step for working on a piece of plexiglass, ideally right before fitting. If you have done an excellent piece of work and carefully smoothed the sides, do not ruin it by scratching it in transport!
Dealing With Multiple Pieces of Plexiglass at the Same Time
As with any other material, it is possible to cut multiple pieces of plexiglass at the same time with the correct setup. You will need to have the pieces correctly aligned on your workbench and clamped down. Shifting pieces of material can cause uneven cuts and the blade going off-center – don’t waste your time, materials, and money through sloppy work!
If you are using your circular saw for a job like this (which puts great demand on the blade), it is more likely to overheat and cause problems for the sheet. Proper preparation is even more important here as it can lead to a lot of wasted materials.
Apply a coolant to the saw before working and take a number of breaks throughout the cut if necessary. Again, if this is not possible, using water to cool down the blade can also be done if it is safe to do so.
As with a singular piece of plexiglass, you will need to use sandpaper to treat the edges after you have finished work with the saw.
Can You Cut Plexiglass With a Circular Saw?
Yes, you can use a circular saw to cut plexiglass. Just make sure to use safety gears, and a marker to mark the line you will cut the plexiglass.
Plexiglass is a versatile material that you can make the most of for any job which requires a transparent panel. Properly setting up your working area, how your circular saw will cut, and how you will cut the material will give a professional finish that will make your finishes clean and professional.
Taking the time to understand how to deal with plexiglass is important. Failing to do so can lead to splintering, severe cracking, or a melted sheet sitting on your workbench. That’s wasted supplies and wasted time.
Remember, maintain the temperature of your tool and you should have very few problems with creating clean, straight cuts in plexiglass.