Acrylic sheets are a tricky material to handle with power tools. They are sensitive to heat, and they can chip or crack as well, depending on the type of plastic you chose for your application.
That said, you can cut acrylic sheets with a jigsaw with the right blade and a bit of patience.
TIP!
It is important to note that jigsaws are better at cutting acrylic sheets thicker than 4 mm (approx. 1/8"). Anything thinner than that, and you’re likely better off making clean cuts using a score and snap method instead.
What Do I Need To Cut Acrylic With A Jigsaw Blade?
To cut acrylic sheets with a jigsaw, you will want a jigsaw with a good range of speed control and a variable speed control will help out a little.
Depending on the type of blade you use, you will find that running the tool at medium to low speeds is usually the best bet, even though blades will be more important than speed, overall.
Which Jigsaw Blades Should I Use?
Heat and friction from the jigsaw blade will easily melt acrylic, and you may find a messy, semi-fused line instead of the clean cut you were expecting.
A little heat, on the other hand will help cut the material more smoothly so it is a balancing act. The real goal is to use a decent blade, not a dull one and a blade that has a tooth count of 10 or higher.
You will also want to use a blade appropriate for acrylic. For cutting acrylic and plastic sheets efficiently, a bi-metal blade with sharp teeth and a medium tooth count (10 - 16) work well at moderate speeds.
Jigsaw blades with finer teeth, on the other hand, need to be used with the jigsaw at slower speeds, as these will quickly heat up in just moments.
Carbide edged blades will give you the finest cuts, in theory, but they also generate heat the fastest and usually aren't the best choice.
In general, jigsaw blades designed for PVC and plastic is the way to go when using a jigsaw to cut acrylic sheets but metal blades can work pretty well too, something in the (14 - 21 tooth range).
What Else Do I Need?
Clamps: You will also need to have a way of clamping the acrylic sheet firmly. Any chattering or vibration can lead to the jigsaw blade ripping up the plastic and ruining the cut.
A guide fence made from a straightedge and clamps will also give you better straight cuts than simply trying to freehand it.
Measuring & Marking: You will need a way to mark the cutting line for your cuts. Some acrylic sheets come with paper backing which can take pencil marks.
For others that come with film, you will need a fine marker instead (dry erase or sharpies work well).
Tape: You will also need some tape to mask off the acrylic where you intend to make your cut. The tape will help prevent chipping when cutting and it can also come in handy on your jigsaw's shoe to prevent the metal from scratching the plexiglass.
A simple masking tape will do for this (i prefer the blue tape myself).
Protection: Finally, you need to have eye protection on at all times when working with hardened plastic materials like acrylic and plexiglass.
How to Cut Acrylic With A Jigsaw (Basic Instructions):
Secure the work piece on the workbench to keep vibration and chattering under control. At the minimum, you should be holding down the two ends of the cut – the more clamps you use, the better the cut will be.
TIP!
When you clamp the acrylic sheet, it would help to make sure you have it sandwiched between layers of wood or MDF boards, and do not clamp them directly on the workbench. This is to protect the plexiglass from scratching when operating the jigsaw.
Do not remove the protective film or paper covering the acrylic sheet (if equipped).
Mark the measurement that you need with two small lines, so you know where to put the tape.
If you are cutting long straight lines using a jigsaw, it pays to set up a fence guide along one side of the cutting line to guide the jigsaw shoe, so you will have to measure the edge of the shoe to the side of the blade and make two more reference lines.
Now you will want to place a piece of tape right on the two reference lines we made, trying to get the center of the tape as close to the reference lines as possible.
You will then want to remeasure and make a solid line, all the way across the acrylic sheet.
Attach an appropriate blade on the jigsaw, and check the speed setting. In general, the more teeth on the blade you are using, the slower you want the tool to run.
For the most part, speed won't affect the cut as long as the blade you are using is the correct one but I prefer a medium speed myself.
Position the jigsaw on one end of the cut, taking care to align the jigsaw on the cutting line. Check that the shoe is set down flat on the surface of the workpiece, and that the blade is not touching the material.
Start the jigsaw and let it run up to speed. Ease it gently into the acrylic sheet, while taking care that you don’t let the heat build up too much.
You can use a coolant to keep the cut cool by squirting water or oil every now and then but it is not necessary in most cases.
Do not push the blade into the cut more than is needed – applying pressure on the leading edge of the cut will cause the blade to generate heat very quickly.
Instead, focus on following the cutting line and keeping the blade and cut cooled down.
Approach the end of the cut carefully and maintain a straight line, even at the end of your cut.
Making A Test Cut Can Be Very Helpful!
If you are working with acrylic for the first time, or if you are unfamiliar with the speed you need to use for the blade you have, it’s always a good idea to make a test cut first.
Take note of the blade you are using and the speed setting your jigsaw is set at, and make a few practice cuts on some scrap pieces of acrylic.
You can also do a test cut on the waste side of the acrylic sheet to see how it goes before working on the final cut itself.
Making an Interior Cut in An Acrylic Material:
To make an interior cut in acrylic with a jigsaw, you will need to drill a pilot hole so you can have a starting point for your jigsaw blade.
You will need to drill a smaller pilot hole to start the process. Gradually use larger drill bits until the jigsaw blade can fit into the starter holes you made.
You can use a large enough diameter drill bit without the need for smaller bits first but it is safer to start smaller and work up to larger ones, to prevent potential cracking.
TIP!
Starting with a large drill bit runs the risk of cracking the acrylic sheet, and the same goes for trying to do a plunge cut with a jigsaw. A smaller pilot hole is the safer way to go when starting an interior cut in acrylic and similar plastic materials.
Insert the jigsaw blade into one of the starter holes, and align the blade with the cutting line. Turn on the jigsaw and let the blade pick up speed, before gently easing it into the path of the cut.
The same procedure goes for cutting out interior shapes as I stated in the above steps, you just have to drill a pilot hole first to have a starting point is all.
Placing tape on the line is recommended too, the picture above does not show this but it is still a good practice and can prevent chipping a1nd cracking in the acrylic sheet.
