Laser Cutter Reminders

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Other Reminders

Note: This page was last substantively edited 01/14/2016. It is YOUR responsibility as a user of the laser cutter to check and make sure there have been no important changes to the laser cutter since that date.

The HackPGH laser cutter is named Trogdor, for its burninating power.

WARNING:

This reminder page is NOT a substitute for being trained on the laser cutter by a qualified HackPgh member.

This reminder page is NOT a substitute for using your brain and taking appropriate precautions.

You MUST closely monitor the laser cutter while it is operating. See "YOU MUST BABYSIT THE MACHINE" below.

Also see step 15, "Pick Up The Fire Extinguisher And Set It Down.

BOOT UP THE MACHINE EARLY

Step one, boot up the workstation as soon as possible, because it takes 5-10 minutes to boot up. The workstation for the laser cutter runs windows.

The laser cutter can cut through up to 3/4" plywood, using 4/5 passes at very slow speed.

The laser cutter's bed is 90cm wide (left to right) by 60cm deep (front to back).

The laser cutter costs $0.25/minute to cover electricity bills and other consumables (mainly the bulb on the laser, which has a finite lifespan based on usage).

YOU MUST BABYSIT THE MACHINE

You MUST closely monitor the machine when it is cutting,

You MUST be ready to hit the BIG RED E-STOP button.

You MUST be ready to take other appropriate actions in case of fire, the laser cutting head getting caught on something, etc.

BIG RED E-STOP BUTTON

The BIG RED E-STOP button is currently working fine. In the event of a problem or emergency, push the BIG RED E-STOP BUTTON to stop the laser cutter.

Note: At one point the BIG RED E-STOP button was in need of maintenance. At that point, the BIG RED E-STOP button had to be manually popped back up, and then the relay inside the machine, underneath the button, had to be tapped to un-stick it and close the relay. This is no longer the case. Do NOT tap the relay.

LASER CUT 5.3

The program that runs the laser cutter on the workstation is an icon on the desktop named "Laser Cut 5.3".

FILE FORMATS

The laser cutter takes SVG or DFX files or a few other formats.

AutoCAD and DraftSight are two programs known to produce good files.

Inkscape can produce DXF files but they usually have some clutter, doubled lines that need to be cleaned up (removed) in DraftSight or some similar tool.

LOADING & CUTTING

Load your DXF onto the workstation. Run Laser Cut 5.3. Open your DFX file

Import your file with "File/Import".

PREPARE YOUR DESIGN IN LASERCUT 5.3

Select all of your design.

Use "Tools/Unite Lines", specify .05 tolerance

Laser Cut 5.3 displays the design with different line colors to indicate layer sequencing.

Select a set of lines, then change the color using the color blocks along the bottom edge.

Make sure you configure the cuts to cut the holes first, before doing the outline of the material. Cutting the outline might cause hard-to-detect shifting of the material, which will make the holes slightly out of line if they're cut after the outline.

Select one of the color lines in the upper right dialog. In the second column "Mode", click on the dropdown and select "Cut" or "Engrave", etc.

Note: Engrave does an area fill inside the lines, instead of just cutting along the line. It is useful for decorative purposes.

Adjust the power and speed for each color.

See the etching chart on the wiki, or the wooden etching chart kept next to the laser cutter workstation, BUT be prepared to have to experiment to find the right settings.

You adjust the depth of the cut by adjusting the power (i.e. intensity of the laser) and the speed the laser moves across the material. The higher the intensity and the slower it moves, the longer the focus point is on that spot, the deeper it cuts.

TEST YOUR DESIGN WITH SIMULATE

Select "Laser/Simulate", to test the design. LaserCut 5.3 will color in the design according to its algorithms, the same as it will run the laser for real.

ZERO THE CUTTER

IMPORTANT: First CHECK the bed of the laser cutter, look for any possible physical interference, anything sticking up from the bed, the cutting head being too low, etc.

Turn the key on the laser cutter.

The laser will zero (move the cutting head to the starting point, back-right corner).

Press ESC on the console.

Z-REGISTER THE MACHINE

Z-register the machine, i.e. adjust the height of the bed relative to the laser cutting head.

Place your material on the bed.

The arrows move the head horizontally (left/right/forward/back).

Press Z to enter vertical mode, where the up/down arrows change the head height.

Press ESC to get back to horizontal mode when you're done.

First, press ESC and use the up/down arrows to lower the bed so you are certain your material is below the cutting head, with plenty of margin of error.

Use the manual focus gauge (little plastic L shape with "72mm For use with 72mm lense" engraved on them) to physically measure the height from the material surface to the laser lense:

Hold the L upside down.

The bottom of the L should rest on the collar around the cutting lead (the lower, blacker ring).

Press Z on the console and use the arrows to adjust the height of the bed.

Press Z and ESC on the console to exit Z-registering.

Press ESC again to exit vertical mode and then use the arrow buttons to move the laser around further, if necessary.

Use the arrows to move the head to the back-right corner of your material.

Look to be sure that nothing in your material (or otherwise) sticks up and will collide with the laser cutting head as it moves around.

Close the lid once you are finished positioning your material.

DOWNLOAD

When the material is centered, click the "Download" button in the right side dialog, bottom button.

LaserCut 5.3 will pop up a dialog "Stand-alone file manager".

Click "Del all" to clear any existing jobs from the laser.

Click "Download current" to send the job you have open in LaserCut 5.3 to the laser cutter.

LaserCut 5.3 briefly pops up a dialog saying "Downloading, please wait", then another dialog saying "Compiling" and so forth.

TEST FOR CENTERED

Press TEST on the console to make sure the material is centered. The laser cutter will move the cutting head around the perimeter of the design. Watch to make sure the red dot doesn't go off the material.

If necessary, press ESC, use the arrows to adjust the starting location of the cutting head, then press TEST again to check.

CHECK THE LENSE IS UNOBSTRUCTED

Look at the laser nozzle to check that the lense is unobstructed, i.e. that no part has fallen out of whack and is between the lense and the medium you're going to cut.

Turn on the air and coolant.

DO NOT USE THE MACHINE IF YOU ARE NOT SURE ABOUT AIRFLOW OR COOLANT.

If the airflow and coolant aren't working, you can overheat and damage the machine.

Turn air and coolant on by turning on power strip on top of the laser cutter. The cooling system will be very noisy.

Make sure there is airflow coming from the laser nozzle.

The coolant system has recently been upgraded. It is in a metal case, to the left of the laser cutter, on the floor. It should show a green line and should show the current operating temperature.

Check that the coolant water is flowing (behind the machine). Gently pinch the rubber hose to feel the vibration of coolant circulating. Note that with the new chiller, if you compress the rubber hose for a moment, the chiller will beep several times. IF YOU HEAR THIS BEEPING WHILE CUTTING, PRESS THE BIG RED E-STOP BUTTON IMMEDIATELY.

If using the new chiller, check the red LED display on the front of the machine. Note this display is in celsius.

THE COOLANT MUST BE LESS THAN 23C DEGREES OR YOU CANNOT USE THE MACHINE.

If using the water bucket chiller, check the white probe thermometer display, sitting on the back, left corner of the machine. The coolant MUST BE LESS THAN 75F DEGREES or you cannot use the machine.

THE LID GLASS PROTECTS YOUR EYES FROM UV/IR.

Close the lid on the laser cutter.

A bright red dot will appear under the laser, this is just the aiming point, the actual cutting laser is bright white.

The blue dot on Laser Cutter 5.3 on the workstation corresponds to the red dot on the actual laser cutter.


SAFETY RECAP

Once again:

  • Check on the lense.
  • Check on the air flow.
  • Check on the coolant flow.
  • Look to be sure that nothing sticks up and will collide with the laser cutting head as it moves around.

DO NOT USE THE MACHINE IF YOU ARE NOT SURE.

Pick Up The Fire Extinguisher And Set It Down.

Literally. Put your hand on it, pick it up, make sure that it's full, put it down. Do NOT skip this step.

START

Press START on the console.

IMPORTANT REMINDER: YOU MUST BABYSIT THE MACHINE.

You must closely monitor the machine when it is cutting, and be ready to hit the BIG RED E-STOP button and take other appropriate actions in case of fire, the laser cutting head getting caught on something, etc.

PAY

When the laser cutter is done cutting, check the time on the console (round up to nearest minute) and multiply by $0.25 to figure out how much you owe for electricity, wear and tear on the laser cutter lense, etc.

PARK, SHUT OFF

Press DATUM on the console to park/zero the laser.

Turn the key to the OFF position.

Turn off the air & coolant power strip.

CLEAN

Remove your material and any scraps.

Clean out the bottom tray of the laser.

SHUT THE LASER CUTTER DOOR AFTER USING. There is still smoke inside it, it will take a while to clear out. We would rather it clear out through the ventilation, rather than into the shop.