Laser Cutter

Intro

The laser was originally owned by Backyard Brains, and has been donated to AHA when they moved out. Thanks! It was also part of a group order, where i3 Detroit received 2 nearly identical lasers, so their own documentation is very helpful. See their Bumblebee laser cutter wiki page.

The cutter has an 80W infrared laser, with a 1200mm x 900mm bed. It essentially burns away small portions of material to make its cuts. Designs are created in or imported into LaserCut 5.3, which is responsible for tweaking and downloading the design to the laser cutter. Specifically, the laser is a Jinan TransonCNC 1490A in a 1490B shell, for easier disassembly when it needs to be moved around. It is well suited to precise and repeatable cuts on flat and relatively thin material, such as for art or particular parts. Materials such as paper, certain woods, or acrylic work well, but some simply won't cut, or are dangerous to cut, such as chlorine-containing plastics.

Safety

There are 3 main safety issues when using the laser cutter. These are covered in the class that is required to use the laser, but are also covered here.

Fire

Because the laser essentially burns material to make its cuts, there is always a risk of fire. Because of this, you must supervise your cuts the entire time, and be prepared to stop the cut if a fire is started. Different materials are at different levels of risk of fire. For example, corrugated cardboard should be avoided, while acrylic and woods seem safer. However, nothing is 100% safe.

In case of fire:

1. Hit the Emergency Stop Button.
2. Open the hood and remove the work piece from the machine if possible.
3. Use the loud noise room fire extinguisher to put out the fire if necessary.

Cutting Unsafe Materials

For unsafe materials, simply put, it is dangerous to cut certain materials with the laser cutter. Please consult one of many materials lists, such as the i3 Detroit or ATX Hackerspace lists. This is easy to manage by knowing what your material is made of, and only using safe materials.

Commonly cut materials that behave well are sheets of acrylic (make sure it's meant for laser cutting), and thin woods. Some woods that are hard or oily may be more trouble than they're worth to cut, or may produce excessive amounts of smoke. Some materials that seem fine, like corrugated cardboard, can be very willing to catch on fire, and should be avoided. Other materials like foil-backed paperboard may cut fine from the paper side, and hardly at all from the foil side. Unsafe materials like PVC, and other plastics containing Chlorine, are absolutely unsafe to cut, as they will produce Chlorine gas when cut.

Damaging the Machine

Using the laser cutter involves moving the cutting head around, but hitting the head against the work piece or ramming it into the bed surface can break the cutting head and require expensive repair. Avoiding this just requires paying attention while manually moving the head in the X and Y axes, and being very careful when adjusting the bed height (Z axis) to not ram the head into the work piece or cutter bed. This also means that only your work piece should be in laser when cutting, so that there isn't anything to run into.

Also, the industrial chiller must be running to cool the laser tube. Without cooling the laser cutter should not be used, as the tube can be quickly damaged without cooling.

Instructions

This is covered in the laser class that is necessary for using the laser, but also included here.

Turning On

All necessary components are wired into the surge protector on the back right part of the machine, so turning them on is just a matter of hitting the red switch on the surge protector. This turns on the fan for the exhaust, the industrial chiller, and the laser cutter itself. The computer itself is on a different outlet, and normally just stays on.

When turning the machine on, make sure that the industrial chiller beeps, and that the fan spins up. The chiller will also have a readout on the front of the current water temperature in Celsius.

Turning Off

Everything is safe to turn off by turning off the surge protector, just like turning the machine on. This turns off the cutter, the fan, and the chiller. The computer is generally left on.

Maintenance

Maintenance should only be done by experienced and qualified laser lords, or with their supervision. Much routine maintenance is easy and safe to do, but the machine is quite sensitive, and repairs are potentially expensive.

Generally the machine periodically needs:

• rails & bearings cleaned and lubricated
• mirrors cleaned
• lens cleaned
• laser tube replaced (as necessary; wear item)
• lower chamber cleaned of cut remnants
• belts and other tidbits replaced as necessary

References

• Software Manual: https://drive.google.com/file/d/0B9x4RIcqwUojamYxMkswT3EwUWtFVWpwMHpZM0ZRN2hyRFdr/edit?usp=sharing
• Machine Manual: https://drive.google.com/file/d/0B9x4RIcqwUojbm5tdzI2ZnFmV291anZBS0RaZGlOVXQweUZz/edit?usp=sharing

FAQ

Put common questions and their answers here!

The i3 Detroit Laser FAQ is a good start/reference.

Old Article

(take stuff from here to make the new article, delete it when you're done!)

• Owner: All Hands Active!
• Who Can Use: Anyone that has taken the All Hands Active Laser class or those authorized by Greg G and Tim M.
• Contact: Mike or the board for information.

How to use this laser cutter

• You must be trained on this LASER before using it. Get trained by taking the class!

• Detailed Checklist for Big Red: http://goo.gl/agZeub

• Simplified Checklist for Big Red: http://goo.gl/jM9vem

• i3 Detroit has a similar laser cutter and a very nice wiki: http://i3detroit.org/wi/index.php?title=Laser_Cutter_-_Bumblebee
  • Their power/speed settings won't correspond with ours, as their cutter is 150 watt, this one is 80.

Cost

$.75 a minute of actual laser time - public $.50 a minute of actual laser time - members

Interesting Issues

1. When running an outline of a Moai head, the laser stopped and started at various points for a very brief moment.
   1. We simplified the outline in inkscape and made sure to unite lines in lasercut 5.3. This helped, but we still stop/start problems with the laser.
2. It appears that if your image/vector file is greater than any dimension of the bed (140cm * 90cm), the software will crash upon opening.

Occasional divets noticed when cutting through acrylic

Material: 3mm Clear Acrylic

• Divet pattern may correspond to honeycomb outline. Suggestions:
  • Mentions reflection issue from honeycomb: http://www.sawmillcreek.org/showthread.php?199099-Knife-table-verses-honeycomb-table
  • Utilizes a different cutting table method: http://www.kernlasers.com/PDF/Magazine%20Articles/Laser%20Engraving%20on%20a%20Larger%20Scale.pdf
  • Mentions proper adjustment of beam as a means of reducing relflection: http://leadershipdilemma.net/tag/5-essential-tips-for-cutting-acrylic-sheets-with-laser/
  • Mentions reducing power and cleaning your grid: http://www.sawmillcreek.org/archive/index.php/t-205172.html
    • Suggests leaving the backing material on your acrylic (possible just back side)
  • Nick suggests just putting a piece of paper on the back side
• Divet Pattern seems to be reduced when:
  • Leave adhesive material backing on Acrylic
  • With 3mm cut at 25% Speed 100% Power.
  • Do a test circle or line first with your material to verify.

Notes specific to the install at AHA

• Water Chiller installed underneath laser. Pull laser forward ~4' in order to access. Be careful to avoid crushing or pulling out tubes for air & water
• Air Compressor installed underneath laser. Pull laser forward ~4' in order to access. Be careful to avoid crushing or pulling out tubes for air & water

What was Ordered

Jinan TransonCNC 1490A in a 1490B shell. (It comes apart easier for the purpose of fitting through our front door)

• We have been told that everything is outfitted to run on standard 120ac (LASER Cutter, Chiller/Pump, and Exhaust)
• LASER Power Reci80W
• Weight: ~450 kg (1000 lbs)
• Equipment Dimension Top Half 192*131*42cm
• Equipment Dimension Bot Half 192*131*70cm
• Working Area 140cm*90cm
• Metal Slat Table
• Motorized up and down table
• honeycomb table
• Red Dot pointer
• Auto Focus
• Extra Reci80W (LASER Tube)
• Extra Lens & Mirror
• Extra Motion Card (Controller)
• Extra Belt - X Axis
• Extra Belt - Y Axis
• Extra Motorized up and Table Belt
• Extra Girdle Belt
• Extra X Motor
• Extra Y Motor
• Extra Z Motors (2)
• LASER Goggles
• CW3000 Water Chiller

Exhaust

• Exhaust Port: 6"
• CFM ~512

Ongoing Maintenance Costs

Regularly Recurring

• Filters
• Activated Charcoal?
• de-ionized water
• LASER Tubes

Occasional

• Replacement Hardware on LASER (Motors, Belts, etc.)

Ongoing Maintenance

• Who is responsible for the work?
• Who is responsible for the costs?

Training

• TBD once we have the machine. See the manuals linked above for "What we know now"