Using the laser cutter

Log, Extinguisher:

Interior (all switches OFF):

Inspect each mirror for dirt, smudges, haze, and dust using a bright light aimed into the mirror box at a 45 degree angle, then look into the mirror via the laser path. Use dust-off to clear dust; if the mirrors are smudged or you see any significant haze, STOP. Machine is not usable until the mirrors are clean. Operating the laser will damage the mirrors or bake on contaminants.
Test free movement of the gantry by gently and slowly moving it left-right and front-back by hand. Inspect the X and Y slide rails for contamination/grit.
Remove anything from the bed of the laser cutter. If the rotary unit is installed, check for sufficient Z-axis clearance between the tip of the laser head and the rotary unit.
Turn on the main power and check that the gantry correctly and smoothly moves to the home position in the upper left corner of the machine. It will home, then move slightly off the home position at a slower speed, and then center the gantry.
Test the emergency stop switch. Everything should power off; the controller, laser, water/air pumps, etc. Twist to re-enable.

Cooling system:

Loosen the top of the water reservoir and visually check the bucket is almost full of water (use a flashlight or phone flash), then replace the cover. Feel the side of the container while turning on the pump; you should feel vibration.
Inspect around and underneath the laser cutter for signs of water leaks (again, use a flashlight or phone flash.)
Turn on the temperature monitor and verify that it is within parameters for cutting. Life of a CO2 laser tube is directly related to how cool it is kept during operation! Until we add a radiator, the reservoir must be cool enough to stay within parameters during the course of your job. (Insert estimates of temperature rise over time here.)

Ventilation:

Material:

Clean your material of dust and residue.
Verify your material is safe for the machine; check the wiki. If you cannot find your material on the list, do not assume it is safe to cut! A more exhaustive list of materials can be found at http://atxhackerspace.org/wiki/Laser_Cutter_Materials#Safe_Materials
Verify the speed and power settings. Remember: a slower cut at a lower power level will result in less scorching than a higher power level at a faster speed.

Move the laser head to where you want the home position (generally upper left corner.) Load your material, making sure it lays flat on the bed and there are no raised surfaces that the head could run into (only cut flat materials!)
Lower the Z axis several turns using the knob inside and to the right.
Using the feeler gauge (which is approximately 6mm thick, if it becomes mislocated), position the object you’re cutting such that there is a tiny bit of play between the head and your workpiece; the feeler gauge should freely slide between the two. DO NOT raise the bed until the feeler gauge is mashed into the piece! The bed is slightly spring-loaded and this will result in your workpiece being too close when you remove the gauge.
Transfer your job to the cutter; verify that the preview is correct.
With your hand on the e-stop switch, press the “FRAME” button to assure you’re cutting the area you think you will
Fire ze laser! DO NOT GO ANYWHERE. This machine does not sense if the gantry jams, and the laser will happily
Wait 15-20 seconds for fumes and smoke to clear before opening the lid. Why? Unless you’re cutting plain, untreated wood - the smoke and vapors almost certainly contain stuff Not Good For You! Plywood and MDF have glues and binders, for example. Paper may have whiteners, dyes, etc.

Inspect the table. If you cut any material, there will probably be residue, but especially with paper or wood. Using a paper towel and alcohol, wipe down the table, flip over the towel to a cleaner surface and wipe again.

Shutdown:

Delete any job files left on the cutter
Mark in the log your name, date, and cutting time used. “minutes used” indicates how much laser time you used.
Leave the water pump on for several minutes to cool down the tube and optics
Leave the ventilation fan on for several minutes to remove any lingering vapors, smoke, particles, etc.
Shut off all power switches and the temperature monitor, and close the lid.

Protips:

Software notes:

DXF files are opened via Import, NOT “Open”
If you receive a “communication error” when trying to transfer to the controller make sure you have the correct laser cutter selected and that it is on. If that doesn't work then there might be a network cable unplugged somewhere. Check that the laser cutter says LAN:ON on the control panel (todo: add a picture).

Last edited by Ed at 12:03am on 16th of May 2019