Laser Cutter Reminders
Laser Cutter for general information, including on laser-safe materials.
Note: This page was last substantively edited 01/02/2019. 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.
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 LASER PC EARLY
Step one, boot up the workstation for the laser cutter as soon as possible, because it takes 5-10 minutes to boot up. The workstation for the laser cutter runs MS Windows.
Laser Cutter Basic Specs
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). That translates to 35.4331" by 23.622" inches.
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). There is a timer attached to the side of the laser cutter (see below) to help you keep track of how much you owe.
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.
Note, any time this page mentions a button to push, if it's on the laser cutter console rather than the PC screen or keyboard, it will be referred to as, for example, "console ESC button".
The laser cutter console has an annoying bit of behavior where sometimes various console buttons don't work because it's in some mode, for example the vertical mode used to do Z-registering.
In normal mode the top line in the LCD will be displayed with light text on a black background. If it's not displayed like that, the arrow button to move the head around, etc, won't work. Generally keep hitting console ESC button until the top line of the LCD shows a black background.
TODO: Confirm that black background is normal mode and not vice versa.
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".
The laser cutter takes SVG or DFX files or a few other formats. Generally DFX is preferred.
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 file onto the workstation. There is usually a USB thumb drive at the workstation to use for these purposes. Use at your own risk (re: viruses, etc).
There is also a shared HackPGH file server that you can use. There is a folder on the laser workstation desktop to open the file server. Check the information on that folder and use your own laptop, etc, to open the shared file server and create a folder there with your name, store your files there and then open the folder from the laser workstation.
Run Laser Cut Pro 5.3.
CHECK LASERCUT PRO DEFAULT SETTINGS
Unfortunately you cannot count on the person who used the laser cutter before you restoring any LaserCut Pro settings to the standard default values we use at HackPgh. So you have to do it yourself.
- laser origin setting
- power and speed setting
- corner power and speed setting
For power and speed, see "Power and Speed Settings in Lasercut 5.3" below. The main point of mentioning it here is that you cannot simply set the power and speed for the parts you care about, you have to make sure that the existing settings make sense.
NOTE: The laser DOES NOT FIRE if the power setting is below 15.
CHECK LASER ORIGIN SETTING
Note: There is also an icon on the top toolbar (I believe fourth from the right) named "Knife Origin Point" that brings up the same dialog. It is obviously supposed to look like a knife. Maybe if you squint right.
Select from the top menu bar Laser/Set Laser Origin
The HackPGH standard default starting point for where the laser starts cutting from is the the top (back) right corner.
Somebody using the laser before you may have changed it and forgotten to change it back to top-right.
In the Set Laser Origin dialog, click on the radio for top, right.
Since the laser bed is horizontal, "top" means towards the back of the bed.
TODO: Add screen shot of Set Laser Origin Dialog
TODO: Add screen shot of Knife Origin icon
IMPORT AND PREPARE YOUR DESIGN IN LASERCUT 5.3
Import your file with "File/Import".
Unite Lines in LaserCut 5.3
Select all of your design.
Use "Tools/Unite Lines", specify .05 tolerance.
TODO: Add screen shot of "Tools/Unite Lines" dialog.
Power and Speed Settings in LaserCut 5.3
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.
NOTE: The laser DOES NOT FIRE if the power setting is below 15.
NOTE: There are two power and speed settings, one for the lines and one for the corners. Make sure that both settings are set properly.
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.
TURN ON THE LASER
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.
RESET THE TIMER
To the right of the key, mounted on the side of the laser is small laser cut box with an LCD showing the amount of laser time used. When you finish using the laser, use the reading on the timer to figure out how much you owe HackPGH for the laser time.
On the LCD screen is thin, wide horizontal piece of plastic. This is the reset key. Press it to reset the timer to zero.
Z-REGISTER THE MACHINE AKA FOCUS THE LASER TO MATERIAL
Z-register the machine, i.e. adjust the height of the bed relative to the laser cutting head. Adjusting the height ensures that the laser's point of maximum focus is where it meets the material.
Place your material on the bed.
The arrows move the head horizontally (left/right/forward/back).
Press console Z button to enter vertical mode, where the console up/down arrows raise or lower the laser cutter bed to change the distance between the head and the bed of the laser cutter.
Press console ESC button to get back to horizontal mode when you're done.
First, press console ESC button and use the console 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-shaped focus gauge upside down.
The bottom of the L should rest on the collar around the cutting lead (the lower, blacker ring).
Press console Z button and use the console up/down arrows to adjust the height of the bed.
Press console Z button and console ESC buttonto exit Z-registering.
Press console ESC button again to exit vertical mode and then use the console arrow buttons to move the laser head around further, if necessary.
PREPARE TO START
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.
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.
WHAT TO DO ABOUT SOFT STOP ERROR
Soft stop error is an obnoxiously cryptic error message that simply means that, given the starting location of the head and the design loaded, part of the design is going to be out of bounds of the cutter bed. Since ramming the laser cutter head into the side of the machine would be a Bad Thing, the laser cutter is refusing to try to do that.
"Soft stop" means the software will stop the head from going past a certain point. If the software fails to stop it, there's a hardware switch that it will hit, that's called a hard stop, but generally you never want it to get to the point of needing a hard stop.
Generally speaking, you:
- Place the material on the bed.
- Use the console arrow keys to position the laser head at the back, right corner of the material.
- Press the console "test" button and the laser head will move in a rectangle that is large enough to enclose your design, starting from the laser cutter's current location.
- If that rectangle takes the laser outside your material, adjust things so it doesn't. Change the material location, or change the head's current location, or get a bigger piece of material, or make the design smaller.
- If you get a "soft stop error" from pressing the console test button, then something about the current settings or the design is basically asking the laser cutter to cut outside the boundaries of the bed. Nine times out of ten it's because somebody changed the "knife origin point" setting, see below.
- If you get a "soft stop error" from pressing the console start button, you forgot to do the "test" step, because you should have gotten a "soft stop error" from the test step first.
- To fix the soft stop error.
- First, check the "knife origin point" setting in Laser Cut Pro on the desktop, and make sure that it's set to the back, right corner. This is the HackPGH standard default setting, but you can change it and sometimes people forget to change it back when they're done. See "Check Laser Origin Setting".
- If the "knife origin point" setting is not set to the HackPGH default of the back, right corner, set it to that and then test again.
- If the "knife origin point" setting is set to the default of the back, right corner and you're still getting a "soft stop error", then you have to visualize how the laser cutter head's current location and your design will work out, figure out where that's going to take the cutter head past the boundaries of the bed, and fix that.
- If you've checked "knife origin point" and reviewed how the cutting head's current location and your design will work and you're still stuck, some other troubleshooting suggestions:
- Resend the configs and design file; on the desktop Laser Cut Pro "Download" dialog box delete the files and then re-download them.
- Load your design file into Corel Draw on the desktop and shrink the design size by 10%, then save, re-import into Laser Cut Pro, re-download to the laser cutter, and try the console test button again.
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 on the air and coolant by using the small, white plastic remote control with gray buttons. It should be on a ring on the key used to turn on the laser cutter, or nearby. Button number 1 turns the coolant and air system on and off. Buttons 2 and 3 do not do anything at the time of this writing.
TODO: upload photo of air & coolant remote control.
The cooling system will be very noisy.
Check For Airflow Coming From Laser Nozzle
Make sure there is airflow coming from the laser nozzle. Open the lid, reach in and carefully hold your hand near the laser nozzle to feel for the air flow.
Then close the lid again. (Always keep the lid closed unless you're actually working with something inside the laser cutter).
Check for Coolant Flow from Coolant System
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.
Checking coolant flow is no longer necessary. Just turn on the air and coolant system and check the chiller console to make sure it's reporting that it's on.
The coolant system will will beep loudly and continuously if there are any problems.
You'll hear the same beep when you first turn it on.
Obsolete Air and Coolant
The following instructions are now obsolete but are retained here for historical purposes.
OBSOLETE: Turn air and coolant on by turning on power strip on top of the laser cutter.
OBSOLETE: 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.
OBSOLETE: If using the new chiller, check the red LED display on the front of the machine. Note this display is in celsius.
OBSOLETE: THE COOLANT MUST BE LESS THAN 23C DEGREES OR YOU CANNOT USE THE MACHINE.
OBSOLETE: 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.
- 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.
Watch For Warning Signs
Read Laser Cutter Warning Signs to learn what warning signs to watch out for.
Reading Laser Cutter Cleaning is also recommended, even if you're never actually going to clean the laser cutter.
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.
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.
The easiest way to pay is to paypal to the same address you use for paying yoru monthly dues.
There is also a locked wooden payment box on the table with the laser cutter workstation.
Remember to reset the timer box on the side of the laser cutter when you're done. The the reset button is a thin, gray, horizontal button on the LCD.
PARK, SHUT OFF
Press console DATUM button to park/zero the laser.
Turn the key to the OFF position.
Turn off the air & coolant power strip.
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.