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tool:laser_cutter:operation_manual

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Laser Cutter Operation Manual

RULES FOR USE

  • Always follow any posted notices.
  • Do not use if there is an out-of-order sign posted, even if everything *looks* OK.
  • Always wear the correctly-rated laser safety goggles.
  • Only use materials on the Approved Materials List. If something you want to cut is not on the list, ask a member of the Laser Cutter Committee *first*. Most likely if it's not on the list, it is *TOXIC* or *CORROSIVE*!
  • Do not operate when the lid or any hatches are open.
  • No alcohol in the laser cutter room, and do not use the laser cutter after drinking.
  • Do not leave the laser cutter room at any time while the laser cutter is in operation, for any reason. It must be carefully observed to mitigate and suppress fires, which are a frequent occurrence.
  • Do not attempt to use materials that may splutter or explode (e.g. anything with high water content).
  • Do not use for scarification or laser tattoos.
  • Do not attempt any repairs, calibration, or maintenence of the laser cutter under any circumstances! The laser cutter is not treated like the other tools at VHS in this manner. The laser cutter is not a do-ocracy.
  • Do not use the Emergency Stop button to power-off the laser cutter in non-emergency situations.
  • Do not use more heat (a combination of power and speed) than is necessary to accomplish a cut or etch.

BACKGROUND INFORMATION

The laser cutter is a RedSail model CM1080; it has a bed area of 100cm x 80cm (1000mm x 800mm, approx 3.2ft x 2.6ft, 39" x 31") and uses a 80W CO2 laser tube. It is capable of both cutting (with vector shapes) and engraving (with raster images), both of which may be used together in a single job.

The Laser Cutter Committee oversees its usage and ensures correct maintenance. If you have any questions or concerns, please contact a member of the LCC.

SAFETY WARNING

The laser cutter is a piece of industrial machinery. The laser cutter is not a printer, it is not an appliance, and it is not a peripheral. It must be treated as such; a potentially very dangerous device. You must remain in within 1m of the Emergency Stop button at all times. It must never be left unattended, even for a minute. Fires in laser cutters are very common, and given that we are in an old wooden building, any fire could quickly engulf the entire building, and the operator must be ready at all times to extinguish a fire as soon as it occurs.

From Adafruit:

We know of four people who have had to essentially replace their laser cutting machine because it caught on fire unattended.
One person had their entire shop burned down because they cut acrylic and left it.

There is a zero-tolerance policy around leaving the laser cutter unattended while in operation, and laser cutter privileges will be revoked immediately.

The single most important aspect of safety when it comes to machinery is respecting the machine. This means taking care of it, being careful in your configuration, testing, and usage, ensuring proper maintenance happens, and keeping a close vigil over its operation. Careless behaviour causes tools to deteriorate fast, which is the primary cause of safety issues.

Laser cutters work by heating the material to the point of burning or vapourization. Your job can change in seconds with the accumulation of energy (heat) in your material. Always monitor your lasing job! Never leave the laser cutter room while your job is running.

At 80W, this is considered a Class 4 laser device - the most dangerous rating possible. It is in fact 160x the minimum rating for a Class 4 device. This is very, very powerful and dangerous.

To make matters worse, CO2 lasers emit completely invisible IR (infrared) laser beams at 10,640nm. There is no way to know where the beam itself nor any reflections are going. The only thing you can do is completely avoid any possibility that the laser energy will leave the laser cutter.

At 80W, it will instantly vaporize the cornea, lens, and/or retina of your eye. You will instantly and permanently lose your eyesight - and while it scars over it will be complete agony. It will boil your eyeball. According to Wikipedia, "A pop or click noise emanating from the eyeball may be the only indication that retinal damage has occurred i.e. the retina was heated to over 100°C resulting in localized explosive boiling". Even indirect exposure to the laser beam (or a scattered part of it) can result in blindness.

To reiterate, this laser cutter is 160 times as powerful as the maximum safety-class that is worth differentiating between; well and truly into the realm of lethality if mistreated.

In short, this is a very dangerous device and must be treated with utmost respect and care. It is absolutely the most dangerous tool most people will ever use.

SAFETY AND EMERGENCY EQUIPMENT

Safety glasses

We have special safety glasses that are specifically rated for use with CO2 lasers. They are completely transparent to visible light, but are opaque to the band of infrared light that the laser cutter operates on. Do not use any other safety glasses with the laser cutter, as they will not provide any protection.

It is important that the safety glasses remain functional, so please be very careful with their care and handling. Always replace them in their protective cases, and never put them lenses-down. These are not typical, cheap safety glasses, and must be ordered online (and still aren't cheap!).

Spray bottle

Small flare-ups while cutting material is common, and for flare-ups that don't self-extinguish quickly, the spray bottle is the first line of defense.

Fire extinguisher

If the spray bottle is insufficient for extinguishing a fire, the fire extinguisher should be used.

It should only be used as a last resort however, as its use will destroy the expensive ($300+) mirrors and lens in the laser cutter. Don't let the price deter you from using it when necessary though - it's better to pay for new mirrors than to burn down the entire laser cutter, building, VHS, and all our neighbours!

You will never be in trouble for using the fire extinguisher, and will not be responsible for any replacement/repair costs. Use the fire extinguisher when necessary.

SOFTWARE

The software used for interfacing to the laser cutter is called EasyCut 5.3, which is a rebranded and pre-configured version of LaserCut 5.3. It is a rather dated program, but is usable. Because its editing capabilities are rather poor, it is recommended that EasyCut is only used for the final steps of setting up the work for the laser cutter, and running the job itself.

Corel Draw is available on the laser cutter PC, and is very useful for converting between file formats. Do not use the laser cutter PC for design work however, as that will stop others from being able to use the laser cutter. The laser cutter PC is only to be used for converting and running jobs on the laser cutter. Use your own laptop to create designs, and load/convert them on the laser cutter PC via USB key.

For CUTTING:

EasyCut takes primarily .ai (Adobe Illustrator) and .dxf (AutoCAD, Inkscape, SolidWorks, Corel Draw). AI files are preferred as they preserve curves better, but in practice DXF is very usable.

  • AI:
    • Use Corel Draw to convert the source .ai file from recent versions of Illustrator to one that EasyCut can load. Select Illustrator 8 as the format. EasyCut will give an error that it only supports v7 files, but v8 will still work.
    • If you must use Illustrator to save the .ai file, save as pre-CS, no compression, no extra features - however you will lose all colour information, making it almost useless.
  • DXF: Save as R13/LT95 or R14/LT98/LT97.
    • DXF has no concept of scale, and you have to select a scale when you *export* DXFs. The laser software (EasyCut) assumes a millimetre scale. In other words, a DXF will give a unit-less dimension of 1.0; and that could be 1 inch, 1m, 1ft, or 1mm for all the DXF format and/or reading software knows. I've never had scale issues when using MM for export from various CAD packages.

For ENGRAVING:

EasyCut takes BMP/JPG/PNG images. They must be 1-bit (black & white dithered, not greyscale), and will need to be scaled appropriately when imported into EasyCut.

General Usage

Corel Draw is a good choice for creating files for use on the laser cutter, or converting existing files into formats that can be used, due to its wide variety of import and export formats. Adobe Illustrator may also be used, but it has limited capability for exporting to the older versions of file formats that EasyCut requires.

The most time-consuming, challenging, and thus error-prone step of preparing a file for the laser cutter is setting up the order and settings for the various parts of the job. In EasyCut these are controlled on a per-layer basis, where an unique colour is considered to be a layer (i.e. all parts that are red have the same settings and are cut together, and all parts that are blue may have different settings and also are cut together). The order is specified by the order the layers appear in a list (the top layer will cut first), and may be re-arranged as required. Generally when you're setting up a job, you will want to cut the smaller and more intricate/interior parts first, progressively working up to the larger cuts, and ending with the outline of the work. You will quickly get a grasp on what this means and how to do identify what parts of a given job must be cut when.

  • Use different colours to indicate different layers. Layers are automatically added and removed as colours are selected.
  • Set the layer order in EasyCut to go from small -> large details, ending with the outline cut (if any).
  • Do not remove the protective film/paper from acrylic before cutting or etching, as the smoke will ruin the finish.

OPERATING THE LASER CUTTER

Getting Started

Some experimentation will be required to get the desired results. Refer to the materials and settings chart for reasonable starting points.

Always bring extra scrap material with you that has identical properties (type, thickness, colour, etc) to what you want to finally lase. Use this scrap to test and verify that the laser cutter, your material, and your designs setup are behaving as you expect.

  • Check for instructions posted on or around the laser cutter, such as notices of troubles or out-of-service signs.
  • Make sure that the Emergency Stop button is not activated. If so, twist it gently to de-activate it.
  • Make sure that the main power key on the top-right of the laser cutter is in the off (turned counter-clockwise) position.
  • Clear the top, bed, and catchment tray of material.
  • Close the lid.
  • Turn the power switch of the transformer box, located in the bottom-right of the laser cutter cabinet, to On. The water cooler should beep as it starts, the air-assist pump will start, and the exhaust fan will also start.
  • Wait at least 5 minutes after power-on as the water cooler must get the water chilled and evacuate all air bubbles from the laser tube (this is critical).
  • Put on the laser-rated safety goggles.
  • Turn the main power key on the top-right of the laser cutter clockwise to turn the laser cutter on.

Running a Job

  • Wear the laser-rated safety goggles!
  • Ensure that the lid is closed.
  • Use the arrow buttons on either the laser cutters control panel or in EasyCut to jog (move) the head to the position that you want it to start at.
  • Do not use any other buttons on the control panel, and especially do not ever adjust the speed nor power settings there (the firmware of the laser cutter is buggy with these - the settings will stick and/or randomly take effect!).
  • Open the lid.
  • Place the material that is to be cut on the bed of the laser cutter.
  • Use the focus gauge to correctly focus the laser beam on your material.
  • Do not touch the mirrors or lens of the laser cutter. If they are dirty, please discontinue use of the laser cutter immediately and let the Laser Cutter Committee know. Using the laser cutter with dirty mirrors or lenses could bake the dirt onto the glass and they will then need replacing!
  • Close the lid.
  • In EasyCut:
    • Click the Calculate button in the top-right corner.
    • Click Download in the bottom-right corner. The Stand-alone file manager window will appear.
    • Do not use Download Config!
    • Click Download current.
    • Close the Stand-alone file manager.
    • Click Run Box just above and to the left of the Download button. The laser head will move in a box at the maximum extents of the job.
    • Be prepared to hit the Emergency Stop button if the laser head runs into the extents of the bed.
    • If the position of the material needs adjustment, open the lid, move the material, close the lid, and click Run Box again. Repeat until acceptable alignment is achieved.
  • Ensure that the laser cutter is clear of material, and all equipment is functioning correctly.
  • When ready, click the Start button in EasyCut.
  • Watch the laser cutter carefully and be prepared to hit the Emergency Stop button if required.

Shutting Down

  • Turn the main power of the laser cutter off by turning the key on the top-right of the laser cutter counter-clockwise.
  • Do not use the Emergency Stop button to power-off the laser cutter. It is for emergencies, and using it as a regular power button will only confuse the next operator as it will appear that there was a catastrophic event prior!
  • Leave the transformer box (and thus water cooler, ventilation fan, etc.) on for at least 5 minutes to cool the laser tube down (this is critical for the lifespan of the laser tube, which is very expensive) and vent any remaining fumes.
  • Clear the laser cutter's top, bed, and catchment tray of any material.
  • Turn the power switch on the transformer box in the bottom-right of the laser cutter's cabinet to Off after at least 5 minutes have past.
  • Turn off the light at the back of the laser cutter room if it is on.
  • Replace the laser safety goggles.
  • When leaving make sure that you lock the door behind you. The laser cutter is the first thing that everyone entering from the back alley sees, and we do get break-in attempts.

Dealing with Flare-ups

Flare-ups happen frequently when using a laser cutter; it's simply the nature of the tool. Most flare-ups will self-extinguish as soon as the laser beam (the heat source) has moved away from the area being cut, or if the laser is turned off (by completing the cutting job, the Stop or Pause buttons being pressed, or by pressing the Emergency Stop button).

If a flare-up has been going for more than a few seconds, or shows any signs at all of fully igniting or burning through the material, immediate action must be taken to stop the fire. Your material/work piece is lost at this point - act quickly and do not hesitate.

  • Hit the Emergency Stop button on the control panel of the laser cutter (the big red button on the front-right corner).
  • Douse the area with the spray bottle.
  • If the spray bottle proves insufficient to extinguish the fire, use the fire extinguisher immediately.

WHEN ISSUES ARISE

  • DO NOT ATTEMPT ANY REPAIRS, CALIBRATION, OR MAINTENENCE OF THE LASER CUTTER UNDER ANY CIRCUMSTANCES! The laser cutter is not treated like the other tools at VHS in this manner. The laser cutter is not a do-ocracy.
  • Stop using the laser cutter immediately, with the Emergency Stop button if necessary.
  • Follow the normal shutdown procedures above.
  • Put a sign on the laser cutter that says "OUT OF ORDER - DO NOT USE"
  • Email the VHS members list to let everyone know that the laser cutter is out of order. Include the following information at a minimum:
    • What is wrong with the laser cutter.
    • What you were doing at the time it stopped working.
    • What the current state/condition of the laser cutter is.
    • What you think needs to be done to fix it.

FURTHER INFORMATION

tool/laser_cutter/operation_manual.1385154170.txt.gz · Last modified: 2015/12/12 14:31 (external edit)

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