Laser Manual

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Contact list


  • Scotty Allen (@scotty on slack)
  • Darryl (@augur on slack)
  • Ruth Grace (@ruthgrace on slack)
  • Kyle (@kylesewing on slack)

Who can use the laser cutter

Only people who have been trained by an official trainer can use the laser cutter, in order to prevent unintended damage to the machine, operator, and Noisebridge.

People that have successfully completed the class:

  • Scotty Allen (@scotty) - Trainer
  • Darryl McAdams(@augur) - Trainer
  • Ruth Grace Wong (@ruthgrace) - Trainer
  • Kyle Ng (@kylesewing) - Trainer
  • Henner Zeller (@hzeller)
  • Adrian Kelly (@akelly)
  • Nick Pisaro (@nickp)

How to get trained to use the laser cutter

  1. Ask a trainer if they will train you
  2. Schedule a time with the trainer
  3. Get trained
  4. Get your name on the list of users before the first time you use the machine

  • maintaining a verifiable list of users
    • users can be found at: URL
  • maintaining a verifiable list of safety? trainers
    • trainers can be found at: URL

Basic Safety

The laser cutter is generally a very safe machine to use. However, as with all industrial machines, you need to treat it with respect. The main safety concerns are creating fires, hurting your eyes or skin, getting crushed by the machine, and creating toxic fumes.

The basics:

  • OPEN THE LID if you see a fire
  • BLOW IT OUT if the fire keeps burning


You can really hurt yourself or burn the building down with this machine. If you follow the safety rules, the chances of you causing this is close to zero. Some materials are very flammable on the laser cutter, and shouldn't be cut. Never cut an unapproved material, or a material that you don't know what it is. A laser beam can also initiate a fire if the speed of the cut is too slow or the laser power is set too high.

Ways to not cause fires:

  • ALWAYS WATCH THE LASER CUTTER WHENEVER IT IS CUTTING AS FIRES CAN HAPPEN. The laser affects your material by heating it. Your job can change in seconds with the accumulation of heat in your material. Never leave the room while the laser is in operation. If you leave the laser unattended, your access to the laser cutter will be permanently revoked.
  • Use reasonable speed/power settings. Start with the recommended speed/power settings for your material. Be patient - resist the temptation to crank the power and speed to rush through your job. This can cause fires.
    • There will be some light when material is cut. This light at the point of lasing may be ok as long as it stays with the motion of the laser. If a flame appears while the laser is in operation, stop your job and try again with lower heat settings.
  • Know where the fire extinguisher is in case of a fire. The ONLY fire extinguisher that should be used on the laser cutter is the halotron extinguisher right next to the laser cutter. Other fire extinguishers are corrosive and will ruin the machine.

How to put out a fire:

  • Push the estop. (To turn the machine back on after the estop was hit, you need to switch the power switch on the right hand side of the machine off and on again).
  • Open the lid.
  • If it's small, try and blow it out.
  • If it's smallish, try and squirt it out with the water squirt bottle sitting on the right hand side of the machine.
  • If that doesn't work, use the halotron fire extinguisher to the right of the laser cutter. Aim it at the base of the flame.

Damage to eyes and skin

The laser beam can instantly and permanently blind you. It can also burn your skin.

  • you don't ever want any part of your body in contact with the beam.
  • As long as the door is closed, you're safe to look at the laser. There are interlocks on the door that help ensure the laser never operates with the doors open. Don't disable them.

Crushing danger

The laser cutter is a dumb machine. It doesn't care whether your hand is in the way when it's moving. The head can move when the door is open. Always make sure everyone's hands are out of the machine before moving the head.

Also be very careful not to crash the head into other parts of the machine. Be very careful when moving the z-axis to not crash the head into the bed, and to not move the z-axis if the focus length acrylic circle is under the lens.


The laser cutter burns the things it's cutting, which can create toxic fumes.

  • ONLY CUT APPROVED MATERIALS. Cutting nonapproved materials can release really toxic gases, including chlorine and cyanide. These are really bad for humans, as well as being very damaging to the laser cutter.
  • The ventilation fan should always be running if the laser cutter is on, even if it's not cutting. It's currently wired such that you can't turn on the laser cutter without the fan turning on, but please make sure it's running.

Care of the machine

Please don't perform any maintenance on the machine (including cleaning lenses/mirrors or aligning mirrors) unless you've specifically trained on it.

The laser cutter is finely calibrated piece of machinery. Please close the lid gently, and do not push or jar the machine at any time. Do not lean or press on the tray - it's fragile, and needs to be perfectly flat for the laser cutter to cut properly. If you take the honeycomb bed or slats out, please be ULTRA CAREFUL with them - put them somewhere where they won't get damaged or warped.

Paying for your laser time

The laser cutter has parts that wear out over time, which can be quite costly to replace, especially the laser tube. A new tube costs several thousand dollars. Thus, we require people to pay for the time on the laser they use, so we can pay for new parts.

To figure out how much time your job takes, press the File button, select your file, and then select Work Time from the menu. It will tell you in hours:minutes.seconds.

Please pay for the cutting time you actually use, even if you end up running your job multiple times.


Overall Workflow

This is the overall structure of the workflow. Each part is elaborated below.

  1. Laser start up
  2. Material setup
  3. Convert file to DXF
  4. Load file onto the machine
  5. Dry run
  6. Cut/Engrave
  7. Laser shut down
  8. Cleanup

Laser start up

  1. Turn on power and ensure that the fan and chiller are running
  2. Move the head as far forward and right as possible, close to the controls

Material setup

  1. Clean the bed of any scraps that may be on it
  2. Move the cut head as far forward and right as possible (near the controls)
  3. Raise the laser head as far up as possible
  4. Raise the bed to the desired height, watching the laser head to avoid crashes
  5. Move the laser head as far back and right as possible
  6. Place material on the bed
  7. Focus the laser (do at least for each distinct thickness, optimally do for each piece of material)

Focusing the laser

Noisebridge has acryllic disks cut to various thicknesses that can be used to accurately focus the laser. Specifically the laser head needs to be locked to 8mm above the surface of the material you're cutting.

  1. Place the material on the cut bed
  2. Move the cut head to the center of the area to cut, watching the laser head to avoid crashes w/ material
  3. Loosen the wing nut and raise the head all the way up
  4. Place the focusing discs on the material under the head
  5. Lower the head until it just touches the focusing disc (8mm above material)
  6. Lock the head in place (tighten the wing nut)
  7. Remove the focusing discs

Convert an image in Inkscape to a DXF file

  1. Load the image into Inkscape
  2. Set the different cut paths to different colors (for controlling settings, etc.)
  3. Save as a DXF. Be sure to make the units be millimeters so that importing later will correctly scale the image.

Debugging DXF Problems

Sometimes exporting to DXF introduces bizarre extra lines. There are two things to try to debug. The first is to convert objects to paths:

  1. Select all the problematic shapes
  2. Path > Object to Path

If this fails to resolve the issue, you can try a more radical solution which will eliminate all bezier paths entirely:

  1. Select all the problematic shapes
  2. Convert bezier paths to lines (Extensions > Modify Path > Flatten Bezier).

Flatness 0.5 is good to start with. Smaller = better approximation of the curves. A lower flatness number takes more time to compute, but also produces a better approximation to the curve.

Sometimes need to select the path's directly with the path tool (but not the points!).

Loading into the laser cutter software

  1. Import the file with File > Import
  2. Resize as needed, tho if the file was exported w/ millimeter units, the software should also import the image with the correct size.
  3. Set the cut order:
      • EITHER Set the cut order to inside-out (Handle > Cut optimize > Inside to outside)
      • OR Manually specify cut order with the Set cut property tool (Edit > Set cutting property). See below for more details.
  4. Set the speed and power for the layers as necessary.
  5. Optionally, simulate the cutting/engraving process.
  6. Download to the machine (Laser Work panel on the bottom right).

Manually specifying cut order

In the Set cutting property window (Edit > Set cutting property), you can manually re-order the cut paths. In the window, you'll see an image of the workpiece, and to its right, two lists of paths. When you first open the window, all of the cut paths are in the left. If you select a path (either in the image or in the list) and click the button labeled ">>", this path will be transferred to the end of the right list of paths. If you click ">>>", all of the paths in the left list will be moved to the end of the right list (preserving order). Similarly, clicking "<<<" will move the right list to the end of the left list. If you select a cut path in the right list, the up and down arrow buttons will reorder that path in the chosen direction.

Loading speed and power settings from library

  1. In the top right panel, double click the layer of interest
  2. Click "Load parameters from library"
  3. Select the library item
  4. Click "Load"

Saving power and speed settings to library

  1. In the top right panel, double click the layer of interest
  2. Make sure the layer is set to the desired parameters
  3. Click "Load parameters from library"
  4. Click "Save as"
  5. Enter a name and optionally some notes
  6. Click "Ok"


  1. Open the simulation window with either Edit > Preview or the toolbar button labelled with a monitor.
  2. Click the Simulation button in the right panel


  1. Select the file to use using the File button
  2. Move the head to the initial guess origin with the arrow buttons
  3. Test the frame with the Frame button adjust origin as necessary
  4. Set the origin by pressing Origin
  5. Test the cut by turning the laser power off and pressing the Start/Pause button
  6. Turn the laser power on
  7. Cut by pressing the Start/Pause button



Cancel a cut/dry run

  1. Pause with the Start/Pause button
  2. Cancel and move back to the origin with the Esc button

Laser shut down

  1. Move the head as far forward and right as possible (near the controls)
  2. Raise the laser head as far up as possible
  3. Let the fan run for a little bit (~30 seconds)
  4. Turn the power off


  1. Remove pieces of material scrap left on the bed
  2. Open the tray door on the front bottom and empty the scraps left there

Calculating work time

On the computer:

  • Open the simulation window (see above). Total work time and time of laser use are displayed in the top right. Donations should be calculated by laser use, not total work time.

On the machine:

  • Whole file: File > Select file > Right Arrow > Work Time > Enter
  • Current run: Pause the cut, then check time at the bottom right

Fusion 360

Fusion 360 is a free CAD (Computer Aided Design) program from Autodesk for designing 3D parts, and arguably the best one currently available. If you're designing something complex on the laser cutter, particularly with multiple parts that need to fit together, I highly recommend it over drawing programs like Inkscape. It also has CAM (Computer Aided Manufacturing) capabilities, which makes it very useful for CNC machining and laser cutting. There's a copy of the software on the laser cutter computer, and you can download it here. It's free as long as you make less than $100k per year using it.


  1. Design a part to be laser cut by drawing a 2D sketch and extruding it
  2. Go to the CAM workspace by clicking the Model button in the top left, then selecting CAM
  3. Select the Waterjet operation
    1. Set Type to Laser Cutting
    2. Select the Cutting Mode. I've only tried Through - Auto, but I don't think the different quality settings do anything.
    3. Look up the kerf of the material you're cutting in the #Known good materials section, and enter that in Kerf Width, or if your material's not listed, cut one a kerf gauge and put the result in the wiki. The kerf changes depending on the thickness, speed and power. Setting a larger kerf width will make your parts fit tighter, and a smaller kerf will make them looser.
    4. Select the contours of your part that you want to cut
    5. Go to the Passes tab, and change Compensation Type to In Computer
    6. Hit OK to close the dialog box, and you can see a preview of your tool path. You can go back to edit it by double clicking the contour operation in the tree on the left
  4. To export to DXF, click the Post Process button, which says G1 G2. Make sure rdworkslaser is selected as your post processor, type a name for the export and hit Post. Then select the folder to put it in.
  5. Import the DXF in RDWorks, and continue with the standard workflow starting at #Loading into the laser cutter software
  6. Fusion automatically orders the cuts from inside out and in the fastest order, so there's no need to do it again in RDWorks.

Advanced Options

  1. If you're using your own computer for the first time and not the laser cutter desktop, you have to enable the laser cutter support which is still in beta, by clicking on your name in the top right, then Preferences, Preview, and checking "CAM - Waterjet/Laser/Plasma cutter support". You will also need to download the custom post processor that we use for this laser.
  2. If you want to specify the order manually in Fusion, you can check Preserve Order under the Passes tab, and then it cuts them in the same order that you selected them.
  3. There's a simulate button to the left of the Post Process button, if you want to do it in Fusion
  4. If you want to disable or tweak the lead ins and lead outs, you can go to the Linking tab. Lead ins and lead outs can fix the bump you get on the side of your part where the laser started and stopped, but they also make extra cuts in your scrap material, which you may want to keep. In this tab you can also specify the Entry Position for each cut path.
  5. You can disable Kerf Compensation by settting Sideways Compensation to Center under the Passes tab, though this is not reccomended


Please don't perform any maintenance on the machine (including cleaning lenses/mirrors or aligning mirrors) unless you've specifically trained on it.

  • TEMP note: some check(s) may be included outside of maintenance so a user can trigger a maintenance notification
  • DON'T - let someone who has been trained do it
  • how to tell if the lens is dirty (or getting old?)
  • how to tell if the mirrors are dirty
    • Cleaning the mirrors
      • ethanol solution? isopropanol? - see manual.
      • fabric must be non scratch - see manual.
  • Checking and performing mirror alignment
    • Safety - remove gratings and any other reflective surfaces before any maintenance that requires disabling the door sensors.
    • TEMP note: in restrospect the alignment was a very dangerous situation. mirror paths were not checked before powering on the laser with the door open with many people around. (or maybe nigel is just insanely good at configuring mirrors... still...
    • Tape test - mirrors 1,2,3 and their corresponding exits. Slightly propped laser tube.
    • vertical/horizontal alignment by brass dial.
  • Checking chiller tank water volume
    • Chiller alarm - what does it mean
    • Checking tank water volume
    • Refilling tank water
  • Cleaning the bed and waste drawer (this section probably should be moved to usage)


  • Don't open front/back passthrough doors (for now)
  • Fire extinguishers - which to use for what fire
  • Approved materials
  • careful when raising bed, dont crash into laser head
  • move laser head out of the way before opening the lid
  • power off the laser before opening the lid ???
  • watch the laser while it is cutting


  • Move the machine further away from the right wall so we can get to the power switch.
  • label the water squirt bottle as for fires and not to remove
  • acquire piece of copper for chlorine materials test
  • acquire vinyl record for testing
  • acquire propane bottle and nozzle

material notes

  • material selection - approved materials list
    • nothing that generates hazerdous fumes, particularly chlorine/formeldahyde
    • no aluminum or other metals (?? ryan claims these can be safely engraved in this machine)
    • nothing reflective
    • size constraints
  • laser configuration - power, speed
    • table of recommmended settings for various materials

How to get a new/novel material approved

  • consensus process
  • chlorine test

Chlorine material test

Before you cut any new material you *must* check that it is safe to cut; specifically that it will not produce chlorine gas when it is burned by the cutting laser. Chlorine is extremely dangerous in its gaseous form and so must be avoided at all costs.

To test a new material, you'll need a sample of the material, a small copper rod (about the thickness of a coat hanger), a pliars, and a handheld propane torch. We'll test for the presence of chlorine by burning a sample of the material in a high temperature propane flame and observe the visible emission spectra. Chrlorine produces a bright green light when burned, and so will be very obvious when you're testing your material.

First, light the propane torch and set it to rest upright on a stable surface. Taking the pliar, hold the piece of copper in the blue part of the flame to heat it. As the copper begins to heat sufficiently it'll cause the flame to turn an orange color. A consistent orange color means that the copper has no residue material on its surface and so is clean enough to use as a test. If you observe non-orange flames when you burn the copper you may need to clean in further, either by waiting for the excess material to burn off, or by scrubbing the surface of the copper when it has cooled.

Once the copper is burning, take the hot copper and melt a sample of the new material onto it. For example if you were testing a new form of plastic you can roll the hot copper rod on the material, melting some of it onto the copper rod's surface.

With this done, place the copper rod back into the blue part of the flame. Observe the colors of the emission spectra from the new material burning. If you observe a bright green color, then the material contains chlorine and thus *must not* be burned further. Ventilate your surrounding area to avoid breathing it in. If you observe no green color as you burn your material sample, then the material is likely safe to use with the laser cutter.

Here is a video example by Zach in NYCResistor with a known good and known bad material:


These materials must not be used in the laser cutter.

Bad materials
Material Notes
PVC Contains chlorine. Will produce hydrogen chloride gas when used which is extremely toxic and also damages the laser optics.
Vinyl Most contains chlorine. Will produce hydrogen chloride gas when used which is extremely toxic and also damages the laser optics.
PVC Foams Most contains chlorine. Will produce hydrogen chloride gas when used which is extremely toxic and also damages the laser optics.
Foam Core Usually made with PVC which is harmful as listed above.
Styrofoam Can cause flash fires
Polycarbonate or PETG Does not cut. TAP plastics sells both this and acrylic. Be sure to read your labels when purchasing material. Lexan is the trade name for Polycarbonate, while Plexiglass is the trade name for acrylic.
ABS Gives of hydrogen cyanide
Metals Cannot be etched by this type of laser. Also is harmful as the reflective surface may cause the laser to be reflected back up to the head, damaging it. If someone claims to be etching metal using this type of laser then they are etching a metal with a plastic coating, anodized surface, or some other etchable surface on top.

Known good materials

These materials are known to be ok for use with the laser cutter. The speed and power of the laser cutter will need to be set appropriately for the material and thickness in use. Below is a table showing the suggested settings when cutting or etching them.

Material Engraving Cutting Scoring Notes
Speed (mm/s) Power DPI Speed Power Kerf Width Speed Power
Acrylic (clear, 3mm) 20 mm/s 55%
Acrylic (clear, 12.5mm) 3 mm/s 55% Focal length is 4mm
Acrylic (clear, 18mm) 6 mm/s 55% Focal length is 4mm; cuts require three passes, don't move piece between passes
Cardboard (4mm) 50 mm/s 15% 50 mm/s 5% Minimum line separation at 50/15 = 1/2mm (see reference cuts for more details)

Sourcing Material

In general, you can get stuff form Amazon, but you have to wait for shipping.

For plastics: Tap Plastics is nearby Noisebridge, but is expensive, eplastics is cheaper but you need to wait for shipping, and Mr. Plastics is cheapest but is in San Leandro.

For woods: Discount Builder Supply is nearby.