Laser Cutting

The laser room is equiped with a Trotec Speedy 300, 80W, CO2 laser capable of cutting, engraving, and marking a variety of materials. Two Windows desktop computers with Adobe Illustrator and Inkscape are available for preparing laser job files.

Certification
The Laser Basic Use & Safety class is a required certification to use this machine.

Trotec Speedy 300


Note: Cutting operations have reduced maximum work area, i.e. cutting along work area perimeter is reduced from listed work area (~1 cm).

Manufacturer's Manual
Manufacturer's Manual

A useful guide for setting up a Trotec laser cutting template file in Illustrator can also be found here, which includes a handy downloadable swatch file with all the RBG color presets. The swatch file can be added to one's Illustrator workspace without needing to be reloaded by selecting it's hamburger (three line) menu and checking "Persistent".

This is also a useful guide to select the right print settings for photo engraving

Drawing Software
We use Adobe Illustrator to create laser cutting and etching jobs--it's the preferred choice for Trotec lasers. Other drawing programs can be used, but you'll have to export the files into AI to send them to the laser.

Design Requirements

 * Drawings must be formatted in millimeters, especially for functional parts.
 * Cut lines in file should be drawn with a width of 0.001 mm.

Custom Trotec Laser Color Swatch for Adobe Illustrator
You can use this color swatch to streamline your color settings while designing. Color swatch file for Trotec online here: Trotec Laser Color Swatch File You can upload it through the 'Other Library' option on the color palette dropdown menu.

Terminology

 * Bitmap - Representation of an image as bits of information (pixels); used to allow logos/stencils to be changed into colors.
 * Trace Bitmap - Can be used on a bitmap to to turn it into a vector.
 * Vector - Representation of an image as shapes, rather than bits; used to allow logos/stencils to be modified as objects.

Trotec Job Control Laser Software
The only software that is able to run the Laser is the manufacturer's Trotec Job Control.

In the case of whatever computer controlling the laser breaks down, a backup of the JobControl ISO is backed up to the internal Fat Cat Fab Lab Google Drive, and can be reinstalled from that.

Approved Materials
These listed materials are tested and approved by Fat Cat Fab Lab for lasering. Not every material on this list can be laser cut, some can only be engraved or marked--see "Considerations / Uses" for details.

Carbon Paper for Black Engraving Tests
If you are engraving on black material, i.e. slate, a nice and affordable test material can be carbon paper, so you're not dealing with inverted designs that would occur with regular paper.

10 power, 35 speed brings pretty reliable results for both vectors and images. It is very flimsy, so double-stick tape onto regular paper can be good as well.

Painting black acrylic onto cardstock paper works better for designs with a lot of shading, but is more difficult to deal with in warping.

Prohibited Materials
Do NOT laser any of these materials. It can cause harm to the machine and any human being in the area.

Where to Buy Materials
Try these places.

Operating the Laser

 * Never leave the laser unattended while in operation! Materials can catch fire so the laser must always be used with attention by the operator and they must stay present in the laser room.
 * The air filter to the left of the laser must be running when the laser is doing a job! Be sure of this sucking out the fumes, otherwise the smoke will damage the lens and mirrors.
 * Always have air assist on for all material settings!
 * Don't forget to focus the lens with the height gauge. The height gauge we have is for the 2" lens!

Lens Types
We have 2" (default) and 4" focal length lenses.
 * The 2" lens is our go to for almost every job. Good compromise between engraving and cutting.
 * Our height guage is for the 2" lens, same with the smaller aperture conical nozzle. Make sure you're using these with the 2" lens.
 * The 4" lens can be used for tall or thick items (ex: foam). Reduced energy density.
 * When using the 4" lens you'll have to use calipers to add 2" to the height gauge (for a total of 4") and effectively hack your own.
 * You must swap the conical nozzle for the one with large aperture to use the 4" lens, otherwise the laser beam will not come out of it!

Print job sits in queue (failed to send) or print driver missing from comp, and can't send job to Job Control
Are you having trouble with sending laser cut files to Job Control?

FIX: The comps have some weird memory issue... don't use Enhanced Geometries for complicated files! Follow instructions below...
 * 1) Delete the failed print job from the printer queue on the comp you're on (comp1).
 * 2) If print driver is missing and/or you can't open Job Control's (JC) Print Preferences menu through Adobe Illustrator (AI), then hop on the other computer next to you (comp2). From comp2, open a simple, known working AI file (ex: 'TrotecTestFile.ai'--use orange magnifying glass search icon) and try to send it to JC.
 * 3) As you do this, open Print Preferences in AI menu and in the JC menu that pops up, UNCLICK 'Enhanced Geometries' and go ahead and send the cut job over as normal.
 * 4) Verify that it appears in JC.
 * 5) Go back to comp1 and reboot it.
 * 6) Ensure that you deleted the failed print job in the print queue (from Step 1).
 * 7) The print driver should reappear and you should be able to access the Print Preferences menu in AI (JC pop up menu). UNCLICK "Enhanced Geometries" and send your print job over.
 * 8) Set your cut settings as normal and laser away.
 * 9) If successful, pat yourself on the back. If failed, cry, send a message to #laser in Slack and tell everyone you broke the laser.

Job Control error "No more room left for jobs"

 * Make sure your job is smaller than 27" x 17"
 * Make sure you're sending your job in the correct orientation.

Laser decides not to cut all, or certain vectors

 * Make sure you don't have overlapping cut lines. This can be caused by using the "Paste in Place" function in Illustrator.
 * In Illustrator:
 * Check your Document Color Mode (duh).
 * Check the dropdown menu in the color tool palette. Confirm that RGB is selected, and not Grayscale or other.
 * Select your vectors and bring up the color dialog. Edit menu -> Edit Colors -> RGB
 * The color Black may not work for cutting, but will work for engraving (really weird)

Laser chamber fills with smoke

 * Check that the air filter is working, by manually toggling the air filter power button. On the airfilter console, this button's icon is a circle with a line through it. If it's not running, stop working and notify the #laser Slack channel or the Board.

Maintenance
See pg 52 for maintanence schedule.
 * Manufacturer Instructions (pg. 52)

We have a laser maintenance log. Please fill out log on wall to left of laser (right of woodshop door) whenever any laser maintenance is done (clean lens/mirror, change filters, etc). This helps us see how often laser parts are maintained and helps us pinpoint if any problems are arising over time.

Lens Cleaning

 * Manufacturer Instructions
 * Manufacturer Instructions (pgs. 47-48)

Lens should be checked daily and cleaned at least once a week, especially by those who cut wood. Be sure chamfered edges of lens matches laser head chamfers with grooved sides upward when inserting lens.

The lens cleaning fluid can be found in the toolbox on the laser. Refills for the lens cleaning fluid can be found in the closer, on the top-most right-most shelf. It's the Lens Clens #1, red.

Mirror Cleaning

 * Manufacturer Instructions
 * Manufacturer Instructions (pgs. 49-51)

Mirror #3 on laser head should be checked daily and cleaned at least every week. (pgs. 49-50) Mirror #2 (right side of laser, inside panel) should be checked and cleaned every week. (pgs 50-51)

Careful not to scratch it since the reflective mirrored surface is on top (not under glass like bathroom mirrors). Be sure chamfered edges of mirror match laser head chamfers when installing mirror.

The mirror cleaning fluid can be found in the toolbox on the laser. Refills for the mirror cleaning fluid can be found in the closer, on the top-most right-most shelf. It's the Lens Clens #2, yellow.

Air Filter Replacements
Our air filter is apparently a Mistral Ecotech 100 made for Trotec (though it definitely says TEKA on it, so Mistral is sus).


 * Changing Trotec Filters

The air filter has 6 different layers and usually the top filter needs replacement about every 2 weeks depending on usage.

The 3 filter pads below that get replaced after 1000 hours. Charcoal is replaced at least once a year (or twice).

From top down, they are:
 * 1) Top filter
 * 2) Cartridge (not currently installed since we're cheap and they're $550)
 * 3) Middle filter
 * 4) Charcoal top filter
 * 5) Activated charcoal ($550 from Trotec, so we use activated charcoal for aquariums)
 * 6) Bottom filter

Replacement Filter Media: Viledon A 3 / 300 S Filter Mat

Trotec Description:
 * "8450 Prefilterset for Active carbon filter" - Part Number 1546 (They'll need to know what size to cut it to--choose largest filter size). But don't buy from them since they charge ~$33 per piece and can be sourced elsewhere for ~$7 per piece. Inquire for a distributor from here: https://products.freudenberg-filter.com/en_US/detail/9481/filter-mats/a3-300-s-filter-mat/

Changing the Top Filter
The dimensions for the top filter are labeled on the filter machine.

Items you'll need:

 * New filter of the right size - in a plastic bag to the right of the laser (there are various sizes in there, labeled). Appropriate filter sizes are labeled on the front of the filter box.
 * Water-filled spray bottle - usually hanging in the laser room on the paper holder to the left of the woodshop door
 * Disposable gloves - above the microwave (at the moment)
 * Respirator - hanging on the woodshop door in the laser room
 * Small garbage bag - under the kitchen sink (don't use the huge black bags cuz they're expensive)

Steps:

 * 1) Move the laptop & laser tool box off the filter box and onto the laser
 * 2) Remove the gray electric cable at the bottom right side of the filter box (by your feet)
 * 3) Pull the filter box towards you about a foot or so until you can reach the black inlet tube (back, top).
 * 4) With your hands grab the black tube firmly and with a twisting motion loosen it backwards (it's held in tightly with friction and a duct tape gasket). Once the tube is removed swing it down to the ground to the left of the laser so you can reach it later.
 * 5) Pull the filter box all the way forward, being mindful of the thin white thermometer cable running to it and the wall.
 * 6) Unclip the two metal clamps at the upper side of the filter box and lift the lid up. The lid hinges follow the left, long side of the filter box.
 * 7) The top filter will be visible. Inspect that it isn't completely brown/black, clogged, and dirty. If it is, then it should be changed. If the log shows it hasn't been changed within the past 2-4 weeks, it's probably overdue.
 * 8) Put on disposable gloves and a respirator.
 * 9) Spray the top of the filter with the water spray bottle. It doesn't need to be soaking, just damp is fine. The idea is to wet the dust so it stays put as you handle the filter.
 * 10) Lift the top filter frame out of the filter box and get the garbage bag ready.
 * 11) Starting at a short end of the frame, pull the filter material out of the edges of the frame and roll the filter up as you go. # Put the dirtied filter in the garbage bag and tie it up. Put that garbage bag into the big trash can in the main lab.
 * 12) Selecting the correct filter size, lay the filter material down in the frame with the blue ink lettering downward. When it's in the correct orientation there will be no wording visible to you.
 * 13) Carefully snug the edges of the filter all around the filter frame to make a tight seal. There shouldn't be a way for air to pass through the frame without going through filter material. Any air gaps here will cause a problem.
 * 14) Place the filter frame back into the top of the filter box with the fresh white filter material side facing up.
 * 15) Close the lid and relatch the clamps.
 * 16) Push the filter box back halfway, reach down and grab the black inlet tube, and with a twisting motion, re-insert it into the back top of the filter box lid. This might be a little cumbersome to do but you'll get it. It's seated all the way when it mostly butts with the enlarged portion of the tube.
 * 17) Push the filter box back all the way, being mindful of the thin white thermometer cable and other cabling behind the filter box.
 * 18) Re-insert the gray electric cable at the bottom right of the machine (the one by your feet you pulled out earlier).
 * 19) Place the laptop and tool box back onto the filter box.
 * 20) Record on the Maintenance Log on the wall: Date / "Top filter changed" / Your Name.

Air Filter Fan Replacement
The filter fan sometimes dies. It can be repaired but is a complete pain in the ass and may require a bearing puller for bearing replacement (we made one). It needs to be replaced with "8450 TURBINE (CONTINUOUSLY RUNNING BRUSHLESS) 115V" which is Part Number 85920 (TRO-900533, ~$870) from Trotec.

The Trotec part is actually a Domel fan supplied by Aigner (aigner.at), but we were unsuccessful finding a way for Domel to sell to us directly.

Replace Honeycomb Bed
Replace when overly worn, dirty, or broken.

Replacement available on eBay for much less than it can be purchased from Trotec. Search for: Aluminum Honeycomb Sheet / Honeycomb Grid Core - 1/2" cell, 24"x48", T=1.00". Other sizes are available--find the closest matching size.


 * 1) Remove old honeycomb from the frame, keeping close track of the bolts.
 * 2) Trim to size if needed.
 * 3) Re-assemble frame.

Beam Alignment
A job for laser gods.

Bed Leveling
Eh, sometimes we shim it. What matters most is that the laser beam is perpendicular to bed in X/Y planes.

Laser Lab Setup
The laser setup is a bit clunky since we're making it so that multiple computers can use a single laser, which is not a normal feature of Trotec JobControl. This section attempts to describe the setup so it can be recreated as necessary,

JobControl uses the "Spool Directory" config to know what jobs to load. JobControls installs its own driver that pretends to be a normal printer.

Essentially, we "trick" the printer driver from the desktops into sending a job to a remote JobControl instance, hosted on the laser laptop.

The lab computers mounts a network drive shared from the computer connected to the laser, at the time of writing is the "X:\\" directory. The laser computer is then accessed by VNC, which should be an icon on the desktop of both computers.

The JobControl executable on each of the laser computers (not laser laptop) should be renamed (ex: ?_bk.exe) to prevent the executable from loading when "printing" a job from Adobe Illustrator.

Laser Maintenance Log Sheet
Replacement Laser Maintenance Log Sheets can be found here: