How to cut acrylic by laser machine ?
In order to get a polishing effect on the cut acrylic, it is best to use cast acrylic rather than extruded acrylic.
You will need to run at high power, low speed (4’8 mm/s) and air-assisted at low levels to generate heat during the cutting process.
Consider using a lens with a longer focal length (2.5 inches or 2 inches).
Many users do not realize that acrylic acid has two types, and even if they have the same chemical formula, they react differently to lasers.
Typical settings for laser cutting acrylic.
Based on the use of a 50 watt co2 laser tube, I use the following parameters to cut acrylic:
Focus on the surface.
Low to medium air power.
A good flow of air across the ground.
3 mm acrylic: 17 mm/s, 58% power.
4 mm acrylic: 13 mm/s, 58% power.
5 mm acrylic: 10 mm/s, 58% power.
6 mm acrylic: 8.5 mm/s, 58% power.
8 mm acrylic: 6.5 mm/s, power 58%.
Tip: before cutting, remove the protective film and wipe the surface with lenses to eliminate any electrostatic accumulation.
If you need laser cutting and carving a product, then you will need to make some compromises.
However, the use of cast acrylic is the preferred solution, because the engraving effect is much better than extruded acrylic, and it is also possible to get a reasonable polishing effect.
Laser Engraving Acrylic: Raster Engraving
Raster engraving is the process where the laser engraves the image line by line, similar to how an inkjet printer would print an image. just scores the surface of the acrylic, leaving a frosted line behind. This process best suits cast acrylic as mentioned above.
Typical settings for Engraving Acrylic
Based on using a 50 watt CO2 laser tube, I use the following parameres for raster engraving cast acrylic:
18% Max/Min power;
Line Interval: 0.15mm
Focus on surface
Low air assist
Good airflow across the surface
80w co2 laser tube laser machine
Acrylic thicknesses: 6mm
Cutting speed: 5mm/s.
Cutting power: 65% 50% 70%.
Cutting focal length: 6mm.
Whether to blow or not: no air.
Problem: cutting acrylic is very troublesome, and it is easy to have problems such as uneven section, a strong sense of concavity and convexity, whitening of cutting edge, and melting edge caused by the reflection of honeycomb plate, and so on.
Compared with the usually glued plywood, acrylic cutting does not seem to be as simple as imagined, and if you want a good effect, it is not according to the cutting parameters of the plank.
In order to cut the acrylic flat, and smooth, the edge does not whiten and the honeycomb board does not reflect, we have carried out a simple analysis of this acrylic cutting test below.
1. The power is set to 65%, 70%.
The minimum power and maximum power are set because the speed of cutting a straight line is faster than that at the corner. We have said that the faster the speed, the lighter the cutting.
Therefore, in order to cut through the sample, we usually set the minimum power and the maximum power.
2. Speed is set to 5mm/s.
We all know that the faster the speed, the higher the processing efficiency, so when we cut ordinary materials, we will increase the power as much as possible to improve the speed, but acrylic is different, too fast speed will make the section not smooth, there is a sense of concavity and convexity, so in order to cut a smooth effect.
When setting the parameters, we need to keep in mind: increase the power and slow down.
3. Do not blow when cutting.
Many people have the problem of whitening when cutting acrylic, this is because he uses blowing when cutting, so if you want to cut a smooth effect, please turn off the blowing, and also remind everyone, when not blowing to cut acrylic, please be there to guard, because, without the flame retardant of strong blowing, the material is easy to catch fire in the cutting process, if you find a fire, please turn off the machine in time.
4. Blade Table.
When cutting acrylic, if we want to avoid the edge melting problem caused by honeycomb plate reflection, we can use the blade table to solve the problem.
To sum up, we know that when cutting acrylic of 6mm, we might as well set the power to 65% Mui 70%, and the speed to 5mm/s. At the same time, we choose not to blow air in the cutting process, and when appropriate, we can use overhead cutting to solve the reflection problem of the honeycomb board.
Of course, but if we want to cut out the frosting effect, we only need to take a simple step, which is to blow on the air so that the cut acrylic will have a frosting effect.
Is it safe to cut acrylic with a laser?
When cutting any plastic, you need to make sure that there is enough extraction to eliminate the smoke generated during laser cutting and carving.
Acrylic smoke (MMA/PMMA) is thought to be less toxic than plastics such as ABS or PVC (to avoid both).
When respiratory concentrations are high, they are still a health risk.
Setting the air boost too low may cause flares or comet tails in the nozzles.
This happens because the acrylic smoke is not cleared fast enough, and the laser ignites the smoke.
It looks spectacular, but as the heat source (laser) is removed, the flame will automatically go out.