Scroll saws are a great tool that can cut a large variety of materials and that includes some metals.
But can a scroll saw cut acrylic? Yes it can, however there are limits to take note of that we have listed below.
- The thickness of the acrylic.
- The type of blade used.
- The speed of the cutting action.
- The pressure applied to the acrylic into the blade.
- The experience of the operator.
That is the short answer and may serve your interests but for a more detailed response we expand each of the items below.
What thickness acrylic can be cut?
There is potential for cutting acrylic to the maximum depth that your saw will allow, however, with a starting point of a thin acrylic sheet every increment of depth you add to the cut the difficulties will only increase and blade selection and cutting speed will play a greater role in a successful outcome. Maximum cutting potential is a guide and not a target. If you are outside this limit, maybe you need a bandsaw.
The type of scroll saw that is in use will play a large part in deciding the thickness of the piece of acrylic that a scroll saw can handle; and the materials that can be effectively cut will vary with the available speeds that the saw can deliver.
Many if not all materials have a sweet spot where blade speed is concerned and if your scroll saw has a fixed speed this will limit the effectiveness of the cutting of every and any material on that particular saw.
The important thing to remember with any scroll saw is that while they are fantastic tools that are capable of very fine detailed work, they also have limitations.
What scroll saw blade is best for cutting acrylic?
There are several variants of tooth arrangement and design that claim to cut acrylic or plastic and while each blade is capable of performing the task the factor that remains the biggest issue with these blades is operator error.
To cut acrylic and in a perfect situation, several blades come to mind. Skip-tooth blades perform well and we have great success with the Pegas MGT #7 when cutting composites of woods and epoxies and/or polyurethanes.
These vary in thickness from ¾ inch to ½ inch and the blades do the job. While this is not acrylic, the properties of the material are similar in density and in hardness.
The difference for us as scroll saw operators to note here is the higher melting point of the resins against the lower melt point of acrylic; this lower temperature has the potential of melting as we cut and the acrylic reforming a bond after the blade has passed.
This is mostly due to operator error and is caused by a build up of friction at the blade.
Lubricants can be used to minimize friction and care should be taken if the saw is also used for fine wooden detail work where residual oils and lubricants can stain and ruin material being cut after the acrylic has been cut.
Saw maintenance is paramount to clean up everything. Instead of liquid lubricants, a layer of plastic packing tape can be applied to the surface before cutting and the glues in the tape act as the lubricant. We find this method quite effective and clean.
Most often though is that acrylic sheets (assuming it is sheet form we are all talking about here) often have a layer of protective plastic that is on both sides to help prevent scratches during handling and this layer has the same effect as the glues on the packing tape.
If this is the case, and the acrylic still melts, then either the blade selection is incorrect, or the blade selection is correct and it is dull.
If using liquid lubricants on a scroll saw, clean it down thoroughly before cutting high quality material on it. Lubricants can stain.
There are blades that have the ability to be inverted and used a second time because the teeth protrude at right angles to the main blade body and allow cuts to be made from the top and the underside.
These are called Crown tooth blades.
They are good for cutting acrylic, but be wary of the marketing on these blades.
The reality of these blades is that they cut in both directions from the start of the first cut, and if the primary cutting face becomes dull the marketing world says that they can be inverted and away you go again, effectively doubling the life of the blade.
What is not taken into account is that when the primary cutting face becomes dull, the secondary cutting face cannot be that far behind it.The only chance of a second go with these blades is if the inverted blade has unused teeth from the first use but the blade may still be fatigued.
The cutting qualities of these blades are not in question, just the claims of a longer life can be debated. We use a blade once, and when it becomes dull we toss it. The metal is likely fatigued and time is wasted changing blades instead of cutting stuff.
What speed is best for cutting acrylic?
The faster you cut stuff the more heat is generated.
This delivers poor results in cut quality in acrylic as well as causing premature blade failure from heat fatigue. The blades start turning a blue color in other words and it is soon followed by the ping of a broken blade. In bad cases the blade can become welded to the acrylic being cut so correct speed matters.
Because there are so many variables involved with this question it is one of those times where the manufacturers recommendations should be a starting point and work out from there.
There is a massive connection here between cutting ability and blade speed. If your scroll saw has a fixed speed there is limited choice on how to approach any given cut, be it into acrylic, wood, or metal.
This means your blade selection needs to be pretty accurate or you may need to have a few of many different types and brands of blades on hand to make up for the extra variability that a variable speed scroll saw gives.
Generally speaking, slow cuts give the optimum results with acrylic however individual results may vary because of scroll saw speed.
Stock a good variety of different blades to suit your saw. Sometimes things just don’t go as planned and a different blade is required.
What pressure should acrylic be cut at?
This is not a trick question. There is a tendency for novice operators to push material too hard into the blade and this builds heat and leads to premature blade breakages.
This can happen with fresh blades as well as dull blades but the dull blade leaves no choice but for the operator to shove the acrylic through instead of allowing the blade to do the work as the sharp blade was designed to do.
Different materials will cause a blade to react slightly different to another and the dull blade or the blade pushed to hard will cause the melt-back-together syndrome. When that happens, either dial back the pressure and take your time or, it’s time for a blade change.
And this leads us to the final piece of the post.
Let the blade do the work.
Does Operator Experience matter?
This is a trick question.
Of course it matters, and it is something that cannot be found on a store shelf. Scroll sawing takes time to figure out and many blades will be broken before you become effective enough to only break some instead of all of them.
It is also a great way to use smaller bits of wood and acrylic for fun ideas that can be shared and given as handmade gifts. There are many ways these machines can be used and cutting acrylic is just one small facet of a pretty big hobby.