Laser Cutter

NOTE: The sections of this document labeled [draft for vote] are currently under discussion, and are not formally approved, but we expect something like this to be approved shortly. 

<callout title=“Danger Will Robinson” type=“danger”> This machine can only be operated under supervision by one of the Laser Supervisors. </callout>

State of Operation

2017-04-04:

Operational, but you still need one of the Laser Supervisors around during its use. Still not safe for use outside of the Laser Supervisors' supervision.

2016-10-16:

Operational, but you will need one of the Laser Supervisors around during its use. Still not safe for use outside of the Laser Supervisors' supervision.

2016-07-05:

Technically operational, but a safety hazard due to dodgy Chinese workmanship. Therefore, it's currently only usable by those qualified in laser safety, handling & operation. nog3, Crofty, pelrun and riumplus have been working to bring it up to a safe standard so it's usable by all. They estimate “three months”. If you ask them nicely one of them may cut something on your behalf in exchange for a donation to the Digital Fabrication Cause, but keep in mind that every hour they spend just cutting stuff for other people is another hour they're not spending improving the machine so everyone can cut stuff themselves. They would totally love some help to make it more widely available; talk to one of them or check out our Trello for our to-do list.

Specifications

  • Machine: RedSail X700 Laser Engraver, Red & Black
  • Power: 60W glass tube, 50W power supply
  • Wavelength: CO2 infra-red 10.6μm
  • Lens: 18mm dia. 50.8mm focal length GaAs lens.
  • Mirrors: TBD
  • Bed size: ~700mm x ~500mm, metal slats. Honeycomb bed will be usable once we have a way of cleaning it
  • Z-axis: ~200mm of clearance, motorised
  • Max speed: 1000mm/s
  • Max resolution: 1000 DPI, 0.01mm recurring location precision
  • Modes of operation: Vector cutting, Vector engraving, Raster fill engraving
  • Thickest material potentially cuttable in multiple passes: 10mm acrylic, 8mm MDF
  • Controller board: Smoothieboard
  • Software: Inkscape for modelling, Visicut to generate the necessary Gcode.
  • Other Features: Liquid cooled with ambient temperature heat exchanger, filtered air intake, exterior-located air extraction system, filtered shop air for the air assist
  • Max Temp of water chiller is 30c, if machine passes this temp it can cause increase chances of cracks in the laser tube.

Induction status

You must be inducted before you can use this equipment. In fact, if you haven't been inducted it's recommended you don't even touch or move this equipment as it's incredibly delicate. Its use is at the discretion of the Laser Supervisors, or by those who are already qualified in Laser Safety, Handling & Operation. See IEC 60825.1 for guidelines, as well as Sam's Laser FAQ. In the meantime, if you need something cut ask one of the Laser Supervisors nicely & one of them may do it for you in exchange for a donation to the Digital Fabrication Cause, but keep in mind that every hour they spend just cutting stuff for other people is another hour they're not spending improving the machine so everyone can cut stuff themselves.

  • Brendan 'nog3' Halliday
  • Aaron 'Crofty' Bycroft
  • James 'pelrun' Churchill
  • Mike 'riumplus' Ando

Safety Considerations

Don't let this happen!

  • When operating this machine, under absolutely NO circumstances must it be left unattended. Not even for just a moment as you get another can of soft drink or duck off to the bathroom. Laser cutters are known for catching fire randomly without warning, even on jobs that they've successfully cut dozens of times before. You need to be there to put it out quickly before a tiny flame that can be just blown out turns into something that calls for the fire extinguisher or worse. If you need to duck away and you can't get anyone else to mind your job for you then you can pause your job, do your stuff, then resume it when you return. It may be boring to be there the whole time but seriously, don't leave it unattended while cutting. See the photo on the right for an example why not.
  • If anything goes wrong, your first port of call is to always bang the big, red Emergency Stop button. It's there for a reason, don't be afraid of using it. Even the resident laser cutter experts have to hit it every so often, because things happen. Don't let the machine self-destruct through your inaction.
  • Lasers are 100% awesome but are 110% dangerous. You are literally cutting, burning, melting and/or vaporising things with a beam of pure, concentrated photons. Treat the machine with the utmost respect at all times because if a serious accident happens that means at best potentially thousands of dollars of damage, and at worst you'll need a trip to the hospital.
  • Along those lines, while you can totally use it to make things that you play with, never “have a play” with the laser cutter. That's like “having a play” with a loaded machine gun. It's a bad idea, even saying it light-heartedly isn't cool. Don't be That Person. If you are caught disrespecting the machine, even verbally, your induction status for this machine will be revoked and you'll have to be inducted all over again before you can use it any more.
  • Try to avoid staring at the cutting point. We know it's pretty & oh-so-mesmerising to watch, but it's very bright & you'll end up with temporary spots in your vision.
  • Only cut approved materials that are known to be safe. If you disobey this rule, you will create toxic fumes potent enough to put you in hospital and/or you'll generate gaseous forms of very strong acids which will literally eat away & dissolve the machine's insides. No that's not a joke or an exaggeration. Don't risk it!
  • The nearest fire extinguisher is by the door to this room. If you use it then the machine will need to be taken out of service as it'll need a proper clean & realignment check by one of the Laser Supervisors; in this case please stop your job immediately, put a Borked or Broken ticket on the machine & post about it on the forums or on Slack. In other words, don't use it unless it's necessary, but if the situation calls for it don't hesitate for one second because a fire will spread very quickly inside the machine. Having to thoroughly clean & align a laser cutter is far better than having to replace a burnt-out shell of an ex laser cutter.

Material choices

There's many things you can use in the laser cutter but many things you cannot. Here's some examples of things that are and aren't suitable, but note that neither of these lists are complete. There are other lists you can find on the internet that may list more materials (but more worryingly many contain inaccuracies). As an example there's a large list by ATX Hackerspace, and another list with more specific individual material details by Pololu.

  • Acrylic/plexiglass
  • MDF
  • Plywood
  • Most woods
  • Paper/cardboard (watch it like a hawk for fires though)
  • Cork
  • Cloth/cotton/felt, aka natural fibre fabrics
  • Natural leather/suede/nubuck (NOT artificial leather). Can be cut if thin, or engraved at any thickness
  • Ceramic tile (engraving only)
  • Glass (engraving only; must be covered in painter's tape first)
  • Any metals of any thickness. Yes, even Aluminium foil. It won't cut any of them, this laser operates at the wrong wavelength, they reflect the beam back through the optics
  • Any material containing Chlorine. This creates gaseous Hydrochloric Acid which dissolves the machine's insides, along with phosgene which is highly toxic (as in, it was used as chemical warfare during WW1)
  • PVC
  • Vinyl
  • Artificial leather, pleather, moleskine etc
  • Polycarbonate/Lexan
  • Polystyrene, including common Polystyrene foam
  • Nylon (it melts & burns)
  • ABS (produces cyanide gas)
  • HDPE/milk bottle plastic
  • Fibreglass, including Carbon Fibre, unless you have an MSDS that states that specific fibre & resin combination are specifically suitable for laser cutting
  • Cutting printed circuit boards (FR4 and other material types)
  • PTFE/Teflon (produces gaseous Hydrofluoric Acid)
  • Food of any description
  • Body parts (I mean really)

Usage Guide

This section is NOT a substitute for an induction, but a quick reminder on the individual steps involved for those who have already been inducted. It's also a guide for a future workflow that doesn't exist right now which we're still creating, so if you try to blindly follow this you'll run into troubles. So don't read this and think that you now know how to use the laser cutter.

  • Make or load your design in Inkscape
  • Send the design to Visicut
  • Position/scale/rotate the design on the bed in Visicut
  • Tell Visicut the material & thickness you are using
  • Tell Visicut which parts of the design to cut and/or which parts to mark/engrave
  • Place the material on the cutter bed and turn on the laser cutter & air compressor
  • Tell Visicut to export the job to the laser cutter
  • Put money in the donation tin
  • Start the job on the laser cutter control panel
  • Do not leave the machine unattended, even for just a few seconds, until it has finished. Get someone else to watch it or pause your job if you need to go to the bathroom etc
  • Once your job's finished, clean the machine (skip this step and you'll need to be re-inducted before you can use the laser cutter again)
  • Take photos of the thing you just made & post them on the forums! We'd love to see what people create & we need more examples of the kind of stuff that's possible with this machine

Inkscape is a free, open-source vector-based drawing application. You can draw your design directly in Inkscape or load it from an existing SVG/AI/DXF/etc file.

You can either draw the whole assembled design on a single sheet sized for material or the bed, or you can draw individual elements that you arrange later on. The second way is easier for simple jobs, because it means that you don't need to worry about the page size or the location of the design on the page at this point, but the first way gives you more control if you need to fine-tune your layout.

If the design combines different types of laser operation (cutting, engraving or rasterised images) then make sure you assign a different colour to each different operation.

Once your design is ready, you can send it to Visicut using the Extensions→Lasercut Path menu item. You have two options - Send to Visicut or Add to Visicut. Selecting Send to Visicut will bed and load just that design on a new, empty bed. Selecting Add to Visicut will add the design to the elements already in Visicut; you can use this multiple times to build up a plate of multiple designs or design elements - say, a whole bunch of gears.

You can send only some objects or elements to Visicut by selecting just those objects when you press the menu item. This is handy if you want to cut just part of a design, or if you haven't already split up the cutting/engraving/rastering objects by colour. You can't separate objects in Visicut, so this is your last chance to differentiate between laser operation modes!

Visicut is a free, open-source laser cutter controller. Each time Add To Visicut is run from within Inkscape, it will create a new item on the build area on the left side of the Visicut window. You can move, scale, rotate or delete each item in this area, which corresponds to the cutting area of the laser cutter.

Note that Visicut is only used once your design is finished. It's not possible to edit an object or split them apart from here; to do that go back to Inkscape, make your edits and resend them back to Visicut.

On the right side of the Visicut window you need to select the material to cut and its thickness, which will load presets for laser power and speed. In the bottom right there's a tabbed window that lets you select which operation to perform on the selected item. This lets you select each vector path in your design for different operations, such as cutting or etching. Which operation is used is automatically decided based on the vector path colour, which is called “mapping”. Sometimes it's easier to colour the elements in Inkscape, send the entire design as one item, then set up a mapping to automatically decide the cutting/engraving/rastering for you, while sometimes it's easier to send the cut elements separately to the mark/engrave elements and configure them individually.

On another tab you can configure the laser speed and power for the cut/mark/raster operations. These are specific to the selected material and thickness, and if you edit them you will update the material profile. Adding new materials or thicknesses is also easy. You shouldn't need to do this if it's a common material, but at this point we're still filling up the list of materials/thicknesses matched to powers/speeds.

Once the design is arranged on the bed properly, put your material on the laser cutter bed. The top-left corner of the design window is the same as the top-left corner of the laser cutter bed, which is also the laser's home position.

You can now close the lid and turn on the laser cutter. After a few seconds you can click the “Execute” button in the lower-right of the Visicut window, which will start the laser cutter and send the job.

Hardware Tips/Quirks

  • Be careful opening & closing the main lid. Don't let it bang shut, as the vibrations can mess up the alignment of the optics.
  • The window to the open paved area next door to HSBNE catches a lot of wind. This is fantastic on a warm day and it's perfect for helping vent the fumes out of the room, but it means rain enters very easily too. And the wooden frame to this window has termite damage. Close this window the moment it starts spitting with rain.
  • The exhaust system extracts the fumes out of the room, but depending on the wind's direction the fumes can blow back inside the nearest green room window. It's common courtesy to close that green room window if the wind is blowing the wrong way before you start cutting & stink out the entire green room.
  • If the temperature on the coolant circulator reads above 29'C then you can't use the laser cutter until it cools down. Note that because it only cools the water down to the ambient air temperature, yes this means that some days in summer when it's 33'C you just can't use the machine. Buying a proper chiller unit is on our wish list, if someone wants to donate or build us one.
  • If you hear a buzzing or beeping alarm, something is wrong - likely catastrophically wrong. Don't ignore it - at any rate, some (but not all) of the alarms will also disable the laser, so you won't be able to continue cutting. Hit the E-stop or pause your job and figure it out before you continue. If you can't figure it out then stop your job, put a Borked or Broken ticket on the machine & post about it on the forums or on Slack.

Maintenance tasks

This machine is very delicate - it's probably the most delicate piece of equipment we own. It also requires a lot of upkeep to keep it running properly. That's where you come in, eager hacker who wants to laser cut some stuff!

  • When your job is finished, small off-cut pieces, aka “swarf”, will have likely fallen below the machine. Open the lower access doors and clean out any swarf that fell below by picking up the pieces, sweeping them up or wiping them up (your choice). These doors are opened by clicking the lever open then pushing the door inwards so the latch falls open - this way the doors won't fall open on you. Do not let the door bang open when you do this as vibrations can upset the machine's calibration. You can open the rear door if you need better access to clean up the rear of the machine.
  • After every job, it's very important to clean the machine of leftover residue to minimise the amount of material that gets deposited on the optics. There are special wipes in a sealed container underneath the machine. Don't be tempted to use these wipes for any purpose at the Hackerspace other than for the laser cutter - they are VERY specially picked wipes to leave no residue behind inside the machine. Use two or three of these to wipe down every easily accessible surface in the machine except the optics. This includes all the metal slats (even if you only cut over a small portion of them), inside the lid, the inside side walls of the machine, the inside rear wall, the entire area underneath the slats, the X & Y gantry rails, etc. Brush clean the extraction grill on the left if it needs it - there's a toothbrush on the tools shelf in this room.
  • To minimise dust in this room, this room needs to be vacuumed with a decent vacuum cleaner regularly. All flat surfaces (eg tables) must be wiped down regularly too.
  • Check the water trap on the regulator at the back left corner of the machine. If there is any water in it, hold a cup underneath it and lift the stopcock on the bottom to drain it.
  • Check the air lines for moisture/oil buildup. The easiest way to do this is to remove the air line from the rear left of the machine and use a screwdriver to temporarily depress the flap inside the nozzle while holding the air line as close to the floor as you can. This minimises the buildup of moisture & oil on the lens.
  • The compressor outside needs to be drained periodically (roughly every few hours of cutting time or fortnightly). Carefully loosen the drain plug on the bottom of the compressor barrel using a shifting spanner. It doesn't need to be completely undone, just enough to let some of the contents escape. Be prepared for dirty water to be blown out under pressure. Once the water is gone, tighten the drain plug again.

This list is primarily here to remind you that if you haven't been specifically shown how to perform the below actions and you don't have the specialised equipment on hand to perform them, you should NOT attempt them. If you think one of these things needs doing, post about it on the forums or mention it on Slack.

  • Cleaning the optics (the mirrors and lenses) - this includes wiping, blowing on them, breathing on them, or anything else that either directly or indirectly touches them. A single piece of dust in the wrong place could shatter them. For realsies - don't touch them unless you have been trained and you have the black plastic briefcase containing the necessary equipment.
  • Adjusting any of the adjustment screws to calibrate the laser beam's alignment
  • Replacing the liquid coolant or bleeding the coolant system
  • Changing any of the underlying software settings on the Smoothieboard or in Visicut. However, changing/adding material settings in Visicut is perfectly okay if you're 100% positive that your new settings are better - please post on the forums with your old settings plus the new settings when you do this so we can track improvements.

Becoming a Supervisor [draft for vote]

Steps that need to be taken to become a “laser supervisor” :

1 - first time using the machine, get shown how its done, by a current “supervisor”, as a spectator only, no touching the machine, but ask as many Qs as you like about the process. ( this is upskilling on the process, and proper/normal working )

2 - second time using the machine, you may operate the machine directly while 100% “supervised” by a current supervisor. , including cleaning. If you are able to demonstrate operating the machine from beginning to end without error, you may proceed to next step. ( this is demonstration of the skills )

3 - third time using the machine, also fully supervised, the supervisor should deliberately introduce a “unknown” fault in a secondary piece of equipment ( eg disable the air compressor ), and the new operator must be able to identify and fix this minor fault without causing equipment damage etc. (this is upskilling on possible/common faults, and how to identify )

4 - the person desiring to become a supervisor must achieve a required number of hours of supervised use like you would with a drivers license. Currently this number is set at 5hrs of “supervised operation”, but may be changed in the future. Users clearly over this number will not be asked to show paper logs, rather it's to prevent “new” users from progressing too quickly to learn common faults.

5 - Complete a decent amount of work on the broken laser cutter to help bring it into service.

6 - Supervisors that train/educate new supervisors are encouraged to question the knowledge and capabilities of the trainee , for example they may be asked to must pass a short 10-ish question test, or demonstrate knowledge about where all the more in-depth knowledge is located, etc.

7 - the person desiring to become a supervisor is required to join the laser-supervisor/s preferred communication/s channel ( the digifab slack channel AND the Digifab Trello board) , and keep up-to-date on issues/faults/rectifications, including being involved in repair of issues where it's within their skill-set and time abilities.

8 - the new “supervisor” is now permitted to operate/supervise the laser without other supervisor/s present.

9 - the new person is added to the wiki page as a “laser supervisor”.

10 - the person desiring to become a supervisor must be willing and able to assist others by supervising them as often as they can.

11 - supervisors list may be revised every 3-6 months at a digifab cause meeting, and will be used to identify if any of the supervisors are currently incapable of continuing to perform the above duties. Supervisors will not be withdrawn from the list ( on the wiki ) without notice.

12 - laser supervisors are required to be actively involved in the Trello / Lasercutter area regularly.

Resources

Showcase of Awesome

For a few pics of out stuff, please goto the next page: Laser Pics Page! (as embedding the images on this page directly broke it )