Tools/laser/induction

From rLab Wiki

Piranha 1060 Laser Cutter Induction

Some of the tools at the Hackspace are potentially hazardous to use, for these tools members are required to have an induction before they can use them. Inductions provide the most basic information on how to safely and effectively use the simpler functions of the tools, we appreciate that some members may have professional experience on some of these tools and in this case please tell your induction provider and the induction may be very reduced and just cover any risks or procedures specific to rLab. Some tools have multiple levels of induction in order to cover more advanced uses of that tool without making the basic induction take too long, higher induction levels will introduce some of the more advanced features of the tools but as with all inductions are only intended to provide basic information on the capabilities of the tools and how to use them safely. Some members of rLab may be willing to offer more detailed tuition beyond basic induction level or offer guided practice sessions in exchange for beer money or assistance on their own projects.

For all tools you are only required to take level-1 induction before use, after that you may perform any task that you feel confident you can do safely, higher levels of induction may be useful to you in performing more advanced operations but are not required before doing tasks covered in them so long as you're confident of your ability to handle those tasks without risk to yourself, others, or the tool.

PLEASE NOTE : All induction providers are volunteers who are providing inductions to the best of their ability but are NOT qualified instructors. Inductions are provided on a best-effort basis but you and you alone are responsible for your safety while using the tools and for satisfying yourself that you can operate the tools safely. There are professional training courses available from various providers in Reading and the surrounding area if you feel they are appropriate for the level of work you intend to undertake. Reading these notes is NOT a substitute for an in-person induction.

Note for wiki editors : Please do not edit induction pages unless you are one of of the people that gives that induction

Introduction

This induction is designed to take a new user through the safe operation of the laser cutter and the basics of the software available to drive it.

Laser Induction

The Piranha 1060 is an industrial laser cutter, using a 90 watt carbon-dioxide laser tube that is focussed through a series of mirrors and a final lens to burn away material placed on the bed by following a pre-set path.

There are a number of risks associated with this and a set of steps necessary to ensure it is operated without damage to the user, the machine or the building.

Any problems or faults should be reported on the RLab Google Group for one of the machine maintainers to investigate. This also lets other users know the machine may not be working.

Health & Safety - Laser Cutter Risks

Risk Description
Fire The cutter works by burning material away. There will be fires. Not might, will.

Fires are caused by :

  • Cutting too slowly through a material
  • Multiple cutting passes through wood – cut in a single pass or it can’t be cut on here
  • Materials likely to burn – Corrugated cardboard, and some acrylics.
  • Debris in the bed of the machine
  • Dirt on the tray of the machine

Materials :

  • Cheaper corrugated cardboard is a high risk for fires.
  • Black foam core board always burns.
  • Loose protective film under the job will burn and keep burning.
  • Replace anything peeling with paper masking tape. Not plastic tape.

Always watch over the job while it is cutting. If you have to leave the room, hit Pause.

Fire fighting equipment is located on the wall and floor on the right hand side of the machine.

In case of a fire :

  • Hit Pause to suspend the job. Does the fire go out ? Continue if safe to do so.
  • If still burning, open the cover and see if you can blow it out.
  • If not, remove the workpiece and use the fire blanket.
  • If the fire blanket is ineffective, escalate to the CO2 extinguisher, then the powder.
  • The powder extinguisher will wreck the machine. This is better than burning the building down though...
  • Last resort – evacuate the building and sound the alarm.
Laser Light

The main risk is direct eye contact. The top cover shields you from exposure. You will not be able to see the laser light. The first indication will be an injury.

There is a gap at the front of the laser for large jobs to be fed through which is not safe to look through.

Do not attempt to look under the workpiece while cutting.

The top cover has interlocks to prevent the laser firing while open. If the laser will not fire, check the red lights on each interlock are lit. There are no interlocks on the side panels or the bed access panel.

The laser focuses at the lens. It is present but diffuse elsewhere in the bed.

It's best not to stare directly at the cutting zone while the laser is running, although it's not likely to cause any serious harm can be very bright when cutting some materials and might not be good for your vision

Distractions

The room is a workspace, not a social area. Ask people to leave if they are causing a distraction from the safe operation of the laser cutter.

Mechanical hazards

Take care with the top cover.

  • You can hit your head on the cover while it is open and you are working in the bed of the laser
  • Things can get trapped between the cover and the machine while it is closing - arms, fingers, tools, etc
  • The gas struts only damp the cover closing - it will still close with some force and quite suddenly

The arm can move at speed, causing injury if you have hands in the bed. There are no interlocks preventing the arm moving while the cover is open. The arm can be moved using either the front panel or the PC.

Set the speed to 100mm/s for a sensible travel rate to position materials etc. Set it to a slower speed for fine positioning.

The bed can also be moved (Z-axis). Take care not to trap anything between the bed and the walls of the laser cutter. This includes the tray that is loose on top of the bed and can slide around.

Fumes

Many materials will give off fumes during cutting. Eg, wood smoke, powders from acrylic.

Plastics can give of nasty fumes.

ABS gives off very nasty fumes.

Leather & rubber will smell very bad, and linger after cutting.

Open the window and doors if necessary. There is an extractor next to the heat pump in the electronics room.

Materials

These materials are dangerous to use in the laser cutter and must not be cut

  • PVC / Chlorides (eg pleather / fake leather, vinyl, modern oil cloth, foamex board). These will generate hydrochloric acid and damage the machine.
  • Fluorides (eg PTFE). These will generate hydrofluoric acid and cause severe damage.
  • Unknown MDF. Older MDF may contain formaldehyde. Safe MDF can be sourced from any reputable DIY store or buy 'laser MDF' for lower smoke.
  • PolyCarbonate. PC will always catch fire, badly
  • Fire-retardant materials. Some fire-retardants contain bromine which will cause damage to the laser and is toxic, don't use fire-retardant materials unless you know for sure what the fire-retarding agent is.

The laser cutter can cut paper, card, many plastics and woods.

It cannot cut metals, but it can surface etch some metals.

Electricity

There are High Voltage and Low Voltage power supplies located under the bed of the machine.

Isolate these supplies properly before cleaning or servicing this area.

The emergency stop button on the front of the machine will kill the power to all supplies. Don't lean on it while you are using the machine...

Water

The laser tube is cooled with a water pump.

The machine will not function if the water supply is not running.

Any leaks from this :

  • Switch off and isolate the system
  • Go downstairs and make sure anyone working underneath knows about the leak
  • Mop up as much as possible
  • Report the fault

Operation

Step Description
Open and check the bed

Look for any loose material, tools etc, check it's clean.

Check the rails are seated properly and not interfering with the Z-zxis movement.

Check the laser head is above the level of the rails.

Power on the laser cutter

Turn on the switch marked '1' on the wall behind the laser cutter.

Press the silver button marked '2' on the front panel of the machine.

The machine will boot and beep when it is ready. If it does not boot, check the emergency stop switch is not pressed in.

Turn on the cooling pump with the switch marked '3' in the stand to the left of the laser. This will beep when switched on.

Put your card into the card reader.

Set the home position.

Press 'Home' then select 'X Y Reset' and 'Enter'

The head will move to the far right corner and the system beeps when it has reset to position 0,0

Press 'Home' then select 'Z Axis Reset' and 'Enter'

The bed will rise to it's upper limit then reset to default cutting position

Seat the material to be cut

The cutter can work anywhere in the bed. It is more precise close to the home position.

The bed is not precisely level. You may need to use some packing to level out the workpiece exactly if you're doing a high-precision job. For most jobs this will not be necessary as the bed is level enough

There is some mesh available for very small jobs. This is a nightmare to clean afterwards.

Set the laser head to the proper height above the work-piece

  • Use the laser focus block to test the height, the maintainers will have left the correct block on the laser
  • Adjust the Z-Axis position, then re-test with the block
  • Do not leave the block in place while moving the Z-Axis. You may damage the head if it runs into the block.

Use the aiming laser to align the workpiece accurately, but turn it off as soon as you're finished with it, it should not be left on while cutting

Leave the top cover open at this point.

Setup the job on the PC

Start LightBurn

Load the job or import from an image

Set the power, mode and speed for each layer

Use the preview tool to check the job looks correct

Use 'Frame' (LightBurn) to test the scale of the job against the position of the material. Caution : These options will move the laser head in the machine - Make sure the machine is clear before using them.

Switch on the laser

When you are happy with the job, close the top cover and turn on the switch marked '4' on the right hand side panel of the laser cutter.

This starts the high voltage power supply and the air-assist pump.

Start the cut

Press 'Start' to begin the cut.

Do Not leave the machine unattended Watch out for fires and make sure the cut is running as planned.

If you get a 'Water Error' on the front panel, check the cooling pump is turned on, and the cover is closed with both interlocks engaged, and that your card is in the reader. If you've checked this and are still getting a "Water Error" message then there is a more complex fault, call for help.

If a large amount of smoke or fume builds up inside the cutter press the "Pause" button to pause the cut and allow it to clear, press it again to resume once the smoke has cleared

When the cut is complete the front panel shows the time taken. Take a note of the time for each cut as this is the time you need to pay for once you are finished and it will be cleared each time a new job is loaded.

After cutting.

Leave the cover closed for a while to allow the extractor to clear the fumes from the machine.

Retrieve the workpiece and remove any loose material that has fallen into the bed.

Once all cuts are complete clean the machine carefully.

Switch off :

  • The laser power (Switch 4)
  • The cooling pump (Switch 3)
  • The laser cutter (Switch 2)
  • Everything else (Switch 1)

Remember to take your card out of the reader.

Cleaning.

Use the gloves and wipes to clean the rails.

Use the wire brush for baked on material on the rails.

Clean the bed as well – wipes, hoover, dustpan etc.

Close the top cover and make sure you have switched off.

Ensure the 6mm focus block is left on the top of the machine for the next user.

Pay up!

The laser costs 20p per minute of cut time as measured for each cut on the front panel. Note that this display resets every time you start a new job so it's up to you to keep a running total.

For commercial / non-member jobs the cost is 40p per minute.

This money covers the cost of replacement lenses, maintenance, and eventually the cost of replacing the laser tube itself when that reaches the end of it's life.

Money goes in the honesty box, or frequent users can fill out a 'laser time' slip and settle up monthly.

Demonstration and Test Piece

Step Description
Check the machine

With the machine off

  • Open and check the bed is clear, clean etc.
  • Show the rails and how to seat them and check they are clean.
Switch on
  • Power on switch 1, note the extractor fan.
  • Power on switch 2, show the laser booting up.
  • Show the card reader, note 'Water Error' is the card is missing.
  • Demonstrate the Emergency Stop button
  • Power on Switch 3, note how long it may take to reach temperature, hot days etc
Set the home position
  • Use 'X-Y Axis Reset' to bring the lens to the home position
  • Show moving the lens to a sensible position to cut
    • Cutting at '0,0' is not a good idea
  • Show setting traverse speed on the front panel
Install test material
  • Find a piece from the scrap pile
  • Show setting the lens height with the focus block
    • Note about running the nozzle into the test block
    • Do not move the bed with the test block in place
  • Show aiming laser operation to align the test piece
Prepare a design
  • Note Dropbox account - dropbox@rlab.org.uk for sharing designs
  • Files on the PC may be cleaned out at any time - it's not a safe place to store things
  • Start Lightburn
  • Show the grid for the bed
  • Import a graphic - note file types
  • Show making a layer for etching
  • Show making a second layer for cutting
  • Show making a third layer for deeper etching
  • Describe cut vs scan modes
  • Set parameters for the three layers
    • Describe power and speed for cuts vs etching
    • Cover maximum and minimum power levels (90% / 12%)
    • Max speed approx 250mm/sec, min speed 1mm/sec
    • Use of a test piece for particular materials
    • Faster speed costs less - charged by the minute
  • Show the preview of a scan layer
    • Can change angle, density etc of the lines
  • Set layer order
    • Etch first
    • Cut last
  • Describe problem with material falling through during cutting
    • Show perforation mode on a cut
    • Show cut and skip lengths
    • Show in the preview tool
Check the job size
  • Use 'Square Frame' to test the size of the job
  • Show the job origin in Lightburn and how this changes the start point, remembering to set the origin mode to "current position"
  • Show resizing the job to fit
  • Show the 'Round Frame' to test an irregular shape
Run a test cut
  • Draw a small square and circle
  • Select the existing layers for cut and etch
  • Use 'Selected Graphics' to just do the test graphics
  • Switch on the laser power with switch 4
  • Run the job
  • Check the cut falls though and the etch is deep enough
  • Adjust layer parameters if required.
  • Error messages you might get
    • Water Error - Water chiller is turned off, lid isn't closed, card not in reader, actual error in water system (call for help)
    • Not Enough Extend Space - Etching too close to one of the edges of the machine
    • Frame Slop - Job doesn't fit in machine (check bed grid), Origin position wrong, origin mode not set to "Current Position"
      • Take care when recovering from a "Frame Slop" error, the head can move suddenly and crash into something, have you hand over the E-stop and don't hesitate to use it!
Run the full job
  • Move the nozzle to a fresh area to re-test or do the full cut
  • Turn off 'Selected Graphics, delete the test square and circle
  • Start the job
  • Describe efficient scan modes
    • Correct scan angle
    • Minimise head travel by splitting into multiple areas
  • Show using 'Pause' to suspend & restart the job
  • Show the job time
    • 20p per minute for normal jobs
    • 40p per minute for commercial / non-member jobs
Check the job
  • Did it cut through
  • Remove the piece
  • Press out any 'Perforation' mode cuts
Clean up
  • Switch off the laser power - switch 4
  • Clean the bed with the hoover, wipes etc
    • Move the head out of the way
    • Use of wire wool etc to remove melted materials
  • Switch off rest of systems - 3, 2, 1
  • Appropriate offcuts to keep, what to throw away
  • Empty the bins if necessary
Payment options
  • Honesty box
  • Laser time slip
  • Direct payment
Induction final cut

Newly inducted member needs to produce a small test piece

  • A cut
  • Some etching

LightBurn Software Notes

LightBurn is 'Better software for laser cutters'

The software can be downloaded from https://lightburnsoftware.com/ but a license key is required after the 30 day trial period ends. RLab has a license for use with our laser cutter.

It is a work in progress, but has more features than RDWorks and is easier to learn for many operations.

Documentation can be found here https://lightburnsoftware.com/pages/lightburn-documentation

File Formats

  • .lbrn - LightBurn native files
  • Vector Graphics. These can be converted to paths and used for cutting.
    • .svg
    • .pdf
    • .dxf
    • .plt
  • Image files. These will be available in Scan mode only to etch onto the work.
    • .jpg
    • .bmp
    • .png
    • .tga
    • .gif
  • Check the 'Import' dialog for the full list.

Modes

Mode Description
Line

Used to cut through the workpiece. The laser will burn through the outline of the selected object.

Use a high power and the fastest speed that will penetrate through the whole material in one pass.

You can also specify 'Perforation Mode' to get the same results as the RDWorks 'Dot mode'. In this instance the 'Cut' setting specifies the length the laser will fire for and the 'Skip' setting is the gap between cuts.

This mode can also be used to etch a fine outline pattern into a workpeice when you don't want to "fill in" the shape and instead just use outlines. In this case you will need to use the highest speed possible (generally around 250mm/sec) and adjust the power to get the strength of line you want

Fill

Used to etch an image or design onto the surface of the workpiece. The laser will fill the interior of the selected object with a series of lines.

Use a low power and high speed setting to burn to the depth required without penetrating the material.

You can specify any angle for the lines to be etched using the 'Scan Angle' setting, and the distance between lines with the 'Line Interval' setting.

There is also a cross-hatch option which will run two passes at 90 degrees to each other. Take care to set the power to a suitable level not to cut through the workpiece on the second pass.

Fill & Line

A combination of the two basic methods that etchs the design then cuts around the outside.

You have two separate power and speed settings to complete, one for each operation.

Layers

Power and mode settings are made using different layers. Each layer is represented by a colour.

LightBurn supports up to 30 layers per job.

The layer menu is under the 'Cuts' tab on the right hand side of the main screen, or from the 'Window' menu if it is not activated.

Double clicking on a colour opens the window to modify the parameters, set the mode, power, speeds etc.

Layers can be enabled or disabled for multiple passes of the laser cutter. In this way you can make overlapping objects and more complex designs.

Layers can be set in a specific cut order using the arrow buttons on the right hand side of the 'Cuts' window. They will run from the top of the list down.

Power Settings

The laser minimum power is 12%. Below this level the tube will not start.

The maximum power is limited to 75%. This is to extend the life span of the tube.

For cutting, try powers at 65% / 75% then set the speed to get the depth of cut required

The laser will cut along the centre of the line with a beam approximately 0.3mm wide. If you need an accurate cut within this resolution, enable the 'Kerf Offset' setting in the Cut Settings window. You can specify a positive or negative value to offset on the outside or inside of the line.

For etching – use a faster speed and lower power.

We do not have a library of suggested settings for different materials. Natural materials will vary between between batches and even between individual pieces so you are advised to run a test on a spare piece before running the final job.

LightBurn does allow you to load a library of materials and power settings that you can create from layers that you are happy with. You can save a personal library in this way and use it to give a head start to finding the correct settings for future cuts.

General Notes

Save your work often…

LightBurn is a work in progress. We have a license that provides updates and these will be applied on a 'when someone remembers' basis. Check the documentation for differences between versions and new features as they are developed.

There are more advanced editing functions available in LightBurn compared to RDWorks. These include

  • Boolean tools to combine and remove overlapping shapes
  • Better tools to auto-join lines together to make a continuous path and construct irregular objects
  • 'Arrange' tools to create arrays of objects and align objects with a set horizontal and vertical offset between them
  • Circular array tools to create copies of an object rotated around a point
  • A large number of different scan and dither settings to produce different graphics effects

LightBurn can also use a camera in the laser cutter to both align the workpiece against the job and import a drawing to make it into a cut or etch path.

There is a basic 'Preview' function which will show an image with the path of the laser head in one colour and the cuts in another colour. This assumes the head is starting at the Home position and you need to use the slider underneath the image to show the order of the cuts across the job.