Laser Cutter

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Why Use the Laser Cutter?

The laser cutter can be used to precision cut some materials up to 0.25 inches thick. The cuts are computer controlled and thus repeatable. A well focused laser with the correct power and speed will cut a kerf of 0.002 inches in 3mm material.

The laser can also be used to mark items by raster scanning an image over the surface. It works in much the way an inkjet printer works, but the laser is used to burn off little bits of the surface of the material to mark the image. The laser is very powerful, but by carefully using a very slight amount of laser power, subtle effects can be achieved.

Access to the Dojo Laser

A Dojo member must successfully complete a Dojo Laser Operation Class before using the laser cutter; this is to keep us all safe and the machine running well. Classes are scheduled on an ad hoc basis. If you would like to attend one, post a note to the #laser channel on Slack.

Reserving the Laser Cutter

Dojo members can reserve time on the laser by using the Book Amenities icon on your HD Dashboard. A Dojo member may reserve up to 3 hours at a time, twice a week, for a total of 6 hours a week. If the machine is not reserved, then other members may use it. If you have used your 6 hours in a week, you should not start long laser jobs - if another Dojo member requests access you should let them have the laser within 30 minutes of when they asked for it.


If you make a reservation and know you won't keep it, then it's your responsibility to the community to remove your reservation from the system - don't tie up the laser for a reservation that you won't use. Also note that if your job starts running long, you should adjust the end time of your reservation. The reservation system is how we communicate; please use it. If someone abuses the reservation system, they could be denied use of the machine.

Laser Support

If you plan on using the laser cutter, join and monitor the #laser channel in the Dojo Slack, also available on your HD Dashboard. You can ask questions or post updates that the community needs to know.

Safety

This machine is dangerous. Used incorrectly it can cause permanent damage to you or other people in the building. As a result of this shared danger, we all have the responsibility to police each other. We each have a duty to question anyone using the laser in a way we feel unsafe. If you are using this machine in an unsafe manner, your laser cutting privileges will be restricted and may result in banishment from the Dojo.

Members are allowed to question any laser cutting operator about the materials they are cutting. If you are operating the laser and someone questions you about the safety of your operation, you should not be offended. If someone asks you to stop what you are doing, for any reason, then you must pause your laser job and discuss their concern. If you cannot resolve the concern between the two parties, then seek out a third party.

Bottom line: No matter what you are doing on the laser, no matter how important your job is, if someone asks you to stop it for a safety concern, you are obligated to stop IMMEDIATELY. If you do not, then yo may lose your access to the laser cutter even if you are later proven correct.

Basic Safety Rules

In general these rules apply to the Makerspace.

  • Do not enter the Makerspace intoxicated.
  • Food and drinks are not allowed in the Makerspace.
  • Do no lean on the tools or machines i.e. the laser cover is somewhat fragile and can bend (our cover is already bent.
  • Wear appropriate attire i.e. close toed shoes; protective clothing or gloves; eyewear, breathing masks or earplugs if necessary.

Operational Safety Rules

This is all covered in the class and documentation, but restated here because it is so important.

  • Never leave the laser cutter unattended.
    • You are responsible for monitoring your work and the safety of the space while you use the tools and machines in the Makerspace.
  • Never cut PVC or chlorinated plastic.
    • You should ALWAYS know what material you are cutting. As the laser cuts/burns some materials can produce highly poisonous and toxic byproducts.
  • Do not try to cut metal in the laser cutter.
  • Complete a routine check before cutting.
    • Check that the lense is clean and that the standard functions are all properly working before starting your cut. If you continue to use the laser in a damaged state it will only make the matters worse.
  • Know how to stop the machine and what to do in the case of a fire.
    • To turn off the laser, simply open the lid of the laser cutter. If you want to keep the lid closed, you can press and hold the pause button.
  • If there is a fire:
    • Open lid to stop the laser.
    • Move the material away from the laser head
    • Press the red emergency stop button on the top right of the machine
    • Use the fire extinguisher (it is located on the wall to the right of the laser cutter).
    • If you cannot put out the fire or feel that you are in danger, call 911

Specific Safety for the Thunder Laser

  • The Thunder Laser will fire one pulse AFTER turning off the power switch. Do not turn on or off the laser until you have closed the laser proof safety cover.
    • Keep your hands and projects away from the laser head while turning on and off this machine.
  • Do not operate the Thunder Laser with the front panel open.
    • Though this machine has the ability to operate with the front panel open, it puts everyone at risk. If this laser is operated with ANY of the covers off the laser can fire. It can bounce off a reflective surface and create a fire anywhere the beam lands. As a result, we do not allow the use of the laser with the front panel open, except in the presence of an expert and with approval from the Hardware Committee.

Materials

The basic cutting controls for the laser are Speed (mm/sec) and Power (% of 100 watts). The first time you use a particular laserable material, check the suggested levels on the printouts next to the laser. These will give you a guideline, but you must experiment with different combinations of Speed and Power to find the best settings for your material.

The "best" combination is one that cuts without burning and without excessive smoking. Start with the suggested Speed and Power and make small test cuts. If they do not cut through increase the Power 10 ppt and reduce the Speed 10 mm/sec. Once the laser cuts through your material, consider increasing the Speed and reducing the Power. Many materials require a certain amount of time to interact with the laser and you will not be able to increase the Speed above a certain point, no matter how much Power you use.

Approved Materials
Untreated Wood (max. 1/4) Plywood/Composite Woods (max. 1/4) MDF/Engineered Woods (max. 1/4) Untreated Paper/Cardstock Cardboard
Acrylic/Lucite/Plexiglas/PMMA (max. 1/2) Thin PolyCarbonate Sheeting (< 1mm) Derlin Kapton Tape (max. 1/16) Mylar (max. 1/16)
Cloth/Felt/Hemp/Cotton Plain Leather/Suede Magnetic Sheet NON-CHLORINE containing Rubber

Approved Etching Materials

  • Glass, ONLY FLAT GLASS
  • Ceramic Tile
  • Anodized Aluminum
  • Painted/Coated Metals
  • Stone/Marble/Granite/Soapstone/Onyx

Restricted Materials

Materials can be dangerous when laser cut or etched because of the poisonous gases generated. DO NOT LASER UNKNOWN MATERIALS. If your material is not on the approved list above, you must have a Material Safety Data Sheet (MSDS) from your material supplier.

  • PVC/Vinyl/Pleather/Artificial Leather
  • Mirrored surfaces
  • Polished materials
  • Thick Polycarbonate/Lexan
  • ABS
  • HDPE
  • Foam
  • Epoxy
  • Fiberglass
  • Coated Carbon Fiber
  • Food
  • Teflon

A third class of materials can be safely lasered but cause such a stench that they are not allowed to be laser cut at the Hacker Dojo. Since the Dojo is a shared space, we must respect the other members. If your laser safe material is generating a lot of unpleasant fumes, then you must stop. Any member of the Dojo may step into the room and ask you to stop. If they do, then you must stop. If you do not stop, you may lose access to the laser cutter.

Class Handout available to anyone who takes the laser training.