Acrylic (PMMA, acrylic glass) is an interesting material that is widely used in manufacturing a variety of products. It’s pretty expensive and needs proper editing.
Today we will look at how to cut acrylic with a laser machine. If you are new to this business, it will help you avoid making mistakes when lasering this material.
Which acrylic glass to choose for laser cutting and engraving?
The two types of acrylic are: cast and extruded. Cast acrylic is well suited for laser cutting. Extruded acrylic is seldom laser cut because it is more prone to cracking than cast. This is due to the creation of post tension that can lead to cracking when exposed to the heat of the laser beam. Less shedding than cast acrylic is one of the advantages of extruded acrylic. However, we do not recommend choosing it for laser treatment due to the high risk of cracking. Cast acrylic is better.
Extraction System: How to Avoid Fire
A properly functioning extraction system must be used when cutting acrylic. Without an exhaust system, the fire risk of the material is very high. Also, when cutting acrylic, the workshop can fill with gasses that can easily ignite or explode. It is dangerous.
Therefore important to monitor the machine. Not recommended to leave the tools unattended or leave the room when cutting acrylic. A Wattsan customer had an embarrassing incident when a machine operator went out to smoke, another employee walked in and unknowingly accidentally touched an air compressor hose. The exhaust system failed and soon he had one car ablaze. Fortunately, the hearthplace came out.
How dangerous is it to process acrylic glass on a CO2 laser machine?
If the exhaust is not working for any reason, it poses a health hazard to the operator. Or when processing acrylic with the machine cover open.
For this reason, it is necessary to check the operation of the exhaust system, ventilate the work area and cut the acrylic with the lid closed.
Features of laser cutting acrylic glass
Selecting a CO2 laser machine, it is recommended to consider the thickness of the acrylic glass to be processed. This determines the power of the laser tube.
Acrylic cut speed parameters must be set manually. Minimizing blowback is also important. Working with the same blow pressure as when processing plywood will produce poor cutting results. The top edge will be rough.
Choosing a blowout pressure, you can use a simple trick to get a mirror-smooth cutting edge. Blow your finger with all your might. Remember how your skin feels. Then set the same pressure on the machine and check with your finger. You can choose a slightly stronger blow, but not weaker. Otherwise, there will be a lot of soot and the machine will quickly fail.
When laser engraving or cutting acrylic, it is recommended to set the machine power to the lowest possible level. A potentiometer can be used for this. When can
acrylic be cut in two passes?
Double passes of acrylic or other materials through a laser machine are not recommended. The power and speed parameters should be chosen so that the material can be cut in one pass.
For example, cutting a 15 mm acrylic sheet requires higher power parameters for the laser tube than cutting 6 mm thick acrylic.
Contour engraving on plexiglass
Remove bubbles when contour engraving on acrylic glass. At the same time, the process should be monitored to prevent escaping gas from igniting. After engraving is complete, the lens should be carefully cleaned to remove any residue of acrylic vapor.
How to remove dirt and efflorescence during acrylic engraving.
Engraving a contour in acrylic creates a white coating. It can be removed using acetone, white spirit, or abrasive paste.
Acetone should be used with caution. Over-wetting the napkin or applying too much force can melt the surface of the acrylic layout.
White Spirit is a popular and fairly inexpensive product. The risk of acrylic melting during processing is lower than with acetone.
Soapy Water Engraving
Soapy Water helps you achieve high quality engraving results. Apply a very thin layer to the material and wait for it to dry. The engraving result is perfect.
Should the foil be removed?
You can leave the foil on the acrylic plate to prevent the formation of a white film during engraving. However, creating a small image makes it very difficult to remove later. Some debris has stuck to the material and the product should be discarded.
It is therefore important to understand the tasks that need to be performed. When cutting large parts, the foil can be left on the acrylic board. You can effortlessly dispose of it later.