Laser Cutter

Intro

The laser was originally owned by Backyard Brains, and has been donated to AHA when they moved out. Thanks! It was also part of a group order, where i3 Detroit received 2 nearly identical lasers, so their own documentation is very helpful. See their Bumblebee laser cutter wiki page.

The cutter has an 80W infrared laser, with a 1200mm x 900mm bed. It essentially burns away small portions of material to make its cuts. Designs are created in or imported into LaserCut 5.3, which is responsible for tweaking and downloading the design to the laser cutter. Specifically, the laser is a Jinan TransonCNC 1490A in a 1490B shell, for easier disassembly when it needs to be moved around. It is well suited to precise and repeatable cuts on flat and relatively thin material, such as for art or particular parts. Materials such as paper, certain woods, or acrylic work well, but some simply won't cut, or are dangerous to cut, such as chlorine-containing plastics.

Safety

There are 3 main safety issues when using the laser cutter. These are covered in the class that is required to use the laser, but are also covered here.

Fire

Because the laser essentially burns material to make its cuts, there is always a risk of fire. Because of this, you must supervise your cuts the entire time, and be prepared to stop the cut if a fire is started. Different materials are at different levels of risk of fire. For example, corrugated cardboard should be avoided, while acrylic and woods seem safer. However, nothing is 100% safe.

In case of fire:

1. Hit the Emergency Stop Button.
2. Open the hood and remove the work piece from the machine if possible.
3. Use the loud noise room fire extinguisher to put out the fire if necessary.

Cutting Unsafe Materials

For unsafe materials, simply put, it is dangerous to cut certain materials with the laser cutter. Please consult one of many materials lists, such as the i3 Detroit or ATX Hackerspace lists. This is easy to manage by knowing what your material is made of, and only using safe materials.

Commonly cut materials that behave well are sheets of acrylic (make sure it's meant for laser cutting), and thin woods. Some woods that are hard or oily may be more trouble than they're worth to cut, or may produce excessive amounts of smoke. Some materials that seem fine, like corrugated cardboard, can be very willing to catch on fire, and should be avoided. Other materials like foil-backed paperboard may cut fine from the paper side, and hardly at all from the foil side. Unsafe materials like PVC, and other plastics containing Chlorine, are absolutely unsafe to cut, as they will produce Chlorine gas when cut.

Damaging the Machine

Using the laser cutter involves moving the cutting head around, but hitting the head against the work piece or ramming it into the bed surface can break the cutting head and require expensive repair. Avoiding this just requires paying attention while manually moving the head in the X and Y axes, and being very careful when adjusting the bed height (Z axis) to not ram the head into the work piece or cutter bed. This also means that only your work piece should be in laser when cutting, so that there isn't anything to run into.

Also, the industrial chiller must be running to cool the laser tube. Without cooling the laser cutter should not be used, as the tube can be quickly damaged without cooling.

Instructions

You must be trained on this LASER before using it. Get trained by taking the class! The class covers all this info, but it is covered here as well

• Detailed Checklist for Big Red: http://goo.gl/agZeub
• Simplified Checklist for Big Red: http://goo.gl/jM9vem

Turning On

All necessary components are wired into the surge protector on the back right part of the machine, so turning them on is just a matter of hitting the red switch on the surge protector. This turns on the fan for the exhaust, the industrial chiller, and the laser cutter itself. The computer itself is on a different outlet, and normally just stays on.

When turning the machine on, make sure that the industrial chiller beeps, and that the fan spins up. The chiller will also have a readout on the front of the current water temperature in Celsius.

Turning Off

Everything is safe to turn off by turning off the surge protector, just like turning the machine on. This turns off the cutter, the fan, and the chiller. The computer is generally left on.

Maintenance

Maintenance should only be done by experienced and qualified laser lords, or with their supervision. Much routine maintenance is easy and safe to do, but the machine is quite sensitive, and repairs are potentially expensive.

Generally the machine periodically needs:

• rails & bearings cleaned and lubricated
• mirrors cleaned
• lens cleaned
• laser tube replaced (as necessary; wear item)
• lower chamber cleaned of cut remnants
• belts and other tidbits replaced as necessary

References

• Software Manual: https://drive.google.com/file/d/0B9x4RIcqwUojamYxMkswT3EwUWtFVWpwMHpZM0ZRN2hyRFdr/edit?usp=sharing
• Machine Manual: https://drive.google.com/file/d/0B9x4RIcqwUojbm5tdzI2ZnFmV291anZBS0RaZGlOVXQweUZz/edit?usp=sharing

FAQ

Put common questions and their answers here!

The i3 Detroit Laser FAQ is a good start/reference.