Laser Cutting

From Fat Cat Fab Lab

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. This is the quiz, where all answers are covered in the class.

Trotec Speedy 300

Trotec Speedy 300 laser cutter and engraver
Trotec Speedy 300 laser cutter and engraver
Trotec Speedy 300 Specifications
Laser Type CO2
Work Area 729 × 432 mm (~28.7 × ~17 in)
Max. Workpiece Height 149.9 mm (5.9 in)
Laser Power 80 W

Manufacturer's Manual

A majority of questions about the laser can be answered in the manual. Please consult the manual if you need help and no one is around to provide an answer.

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

Color Palette

Name R G B Hex
Black 0 0 0 #000000
Red 255 0 0 #FF0000
Blue 0 0 255 #0000FF
Desert 51 102 153 #336699
Cyan 0 255 255 #00FFFF
Green 0 255 0 #00FF00
Grass 0 153 51 #009933
Forest 0 102 51 #006633
Olive 153 153 51 #999933
Brown 153 102 51 #996633
Walnut 102 51 0 #663300
Plum 102 0 102 #660066
Purple 153 0 204 #9900CC
Magenta 255 0 255 #FF00FF
Orange 255 102 0 #FF6600
Yellow 255 255 0 #FFFF00

File Preparation

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.

Fat Cat Fab Lab Laser Approved Materials
Type Material Considerations / Uses
Foam Polyester (PES)
Polyethylene (PE) Not HDPE foam!
Polyurethane (PUR)
Food Gingerbread Do not eat! Laser cabinet is contaminated!
Paper Carbon Paper Affordable test material for testing etching on black material (ex: slate). See section Carbon Paper for Black Engraving Tests.
Cardboard
Cardstock
Chipboard
Foamcore
Museum Board
Paper
Velum
Plastic Acrylic Mirrored acrylic: Laser mirror side down, or cover top with tape if there is no dull side.
Cellulose Acetate
Delrin Provisonal. Needs a test to be accepted.
Heat Transfer "Vinyl" (PET) Siser EasyWeed brand only! It's a PET composition, not vinyl.
Kapton
Melamine
Mylar
PET Not PETG!
Polypropylene
Rubber For stamps. Johnson Plastics Low Odor Laser Rubber only!
Wood Balsa
Birch
Cedar
Cork
Maple
Oak
Pine
Plywood
Poplar
Tape Kapton Tape
Masking Tape
Painter's Tape
Textile Cotton
Leather Vegetable tanned only!
Linen
Polyester Best with 5% cotton blend. 100% polyester may catch fire.
Wool
Stone Concrete
Granite
Marble
Glass (engrave) All Glass Engrave only.
Engraving Laminate ADA Applique Rowmark brand.
ADA Substrate Rowmark brand.
FlexiBrass Rowmark brand.
FlexiColor Rowmark brand.
LaserLIGHTS Rowmark brand.
LaserMag Rowmark brand.
LaserMark Rowmark brand.
LaserMark Reverse Rowmark brand.
LaserMax Rowmark brand.
Textures Rowmark brand.
Metal (mark) Anodized Aluminum Mark only.
Brass Mark only. Must be treated first.
Ferrous metals Mark only. Must be treated first.
Miscellaneous Borax + Water Solution Treatment to create dark black engravings on wood.
Dry Moly Lube Spray Treatment for steel to mark it.

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.

Prohibited Materials
Material Notes Consequence
ABS Possible death. Releases cyanide gas and will likely catch fire.
Coated Carbon Fiber Noxious fumes.
Fiberglass Noxious fumes and can't be cut.
High-Density Polyethylene (HDPE)
Medium-density Fiberboard (MDF)
Nylon
Pleather Synthetic leather
Polycarbonate/Lexan PC absorbs IR light. Cuts poorly and can catch fire.
Polyethylene Terephthalate Glycol-modified (PETG) Too smokey and stinky.
Polypropylene Foam Melts and catches fire.
Polystyrene Foam Catches fire.
Polytetrafluoroethylene (PTFE)
Polyvinyl Chloride (PVC) Includes vinyl, artificial leather, etc. Possible death and destroys laser. Releases chlorine gas which quickly corrodes optics and metal machine components and also humans

Where to Buy Materials

Try these places.

Where to Buy Materials
Type Material Source Thickness Sizes Cost Location Notes
Paper Carbon Paper Amazon Online
Plastic Acrylic Makerkraft (Beadkraft) 1/16" (1.5mm), 1/8" (3mm), 1/4" (5.6mm) 12"x12", 12"x24", 16"x29", 18"x24", 48"x96" Best price in NYC 146 W 29th St, Flr 2 Ken delivers to FCFL!
Acrylic Canal Plastics Center 1/16" (1.5mm), 1/8" (3mm), 1/4" (5.6mm) 345 Canal St
Wood Basswood Blick 1/4" (6mm) 6"x24" $10 21 E 13th St, 650 6th Ave Not too much issue with warping. Note that this is solid wood, not plywood.
Plywood Blick 1/8" (3mm), 1/4" (6mm) 12"x24" $3.63 21 E 13th St, 650 6th Ave The label does not indicate the type of wood. Some pieces are warped but you can look before you buy and pick good ones.
Plywood Woodpeckers, via Amazon.com 1/8" (3mm), 1/4" (6mm) 12"x24", or 18"x24" if you remove the extra 1" with the bandsaw $5.50 Online This is Baltic birch plywood. Some pieces had warping issues, still somewhat usable but not great.
Various Fancy Wood Ocooch Hardwoods 1/16" (1.6mm) to 3/4" (19mm) 4" to 12" Varies Online Check them out online!

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!

Troubleshooting

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?

Note that large files (lots of lines/shapes) can take some time (~10min+).

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.

Job Control error "No feedback from exhaust"

  • When you see this error message, it can help to reset the exhaust unit by holding down the "+" and "-" buttons simultaneously for 3+ seconds on the bottom front of the exhaust unit.

Job Control error "No response from engraver"

  • Full error can be "Check if engraver is connected to the correct COM port and switched on"
  • Obviously, make sure the Laser Cutter is on first and try again. If it is already on, check to see if there are TWO tasks (in task manager/bottom Windows task dock) for the Job Control program. If there are, quit/close one and try again.

Laser decides not to cut all, or certain vectors

  • Make sure the lens is facing the right way (beveled edge facing towards you)
  • 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
    • Any cutting colors, make sure your lines are 0.01 mm or smaller -- the Job control will just ignore thicker lines
  • The color Black may not work for cutting, but will work for engraving (really weird)
  • Make sure there are no images (png, jpg, etc) in the document with the cut vector.

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.

Laser light not visible during focusing

  • Check to make sure the lens is not installed backwards. The chamfered edges of the black lens housing should be flush with the chamfered edges of the laser head.
  • Unscrew the nozzle cone and make sure it is clean and clear of crusty stuff.
  • If the 4" lens is installed, make sure to swap the nozzle cone with the large aperture nozzle cone in the red/white box of laser supplies.

Maintenance

Laser Maintenance Log
Laser Maintenance Log

See pg 52 for maintanence schedule.

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.

Maintenance Schedule
Component Daily Weekly Monthly Other Interval
Laser Mirror #3 (on head) Check. Clean if required. Clean if required.
Mirror #2 (right side) Check. Clean if required.
Mirror #1 (in back) Check. Clean every 6 months.
Honey Comb Bed Check. Replace when worn.
Laser Tube Replace ~5 years.
Exhaust System Top Filter Check. Replace if required. Replace if required.
Middle Filter Replace as needed with charcoal change.
Bottom Filter Check. Replace if required. Replace as needed.
Charcoal Replace every 6 months.

Lens Cleaning

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

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 month. (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).

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:

Mistral Manual and Circuit diagram:

Mistral Operating Instructions
Mistral Circuit Diagram

Changing the Top Filter

The Top Filter needs to be changed every 2 weeks.

The dimensions for the top filter are labeled on the filter machine.

  • Top Filter: 13.5" x 25.5"
  • Middle Filter: ?... we'll get around to adding this dimension...
  • Bottom Filter: 14.5" x 26.75"

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.
  12. 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.
  13. 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.
  14. 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.
  15. Place the filter frame back into the top of the filter box with the fresh white filter material side facing up.
  16. Close the lid and relatch the clamps.
  17. 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.
  18. Push the filter box back all the way, being mindful of the thin white thermometer cable and other cabling behind the filter box.
  19. Re-insert the gray electric cable at the bottom right of the machine (the one by your feet you pulled out earlier).
  20. Place the laptop and tool box back onto the filter box.
  21. 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 to ~$1508) 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.

Sometimes when the fan 'dies' it's actually because it needs to be cleaned. This is due to the filters being changed an insufficient amount and the fan getting clogged.

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.

Where to buy Cleaning Supplies

Where to Buy Cleaning Materials
Name Source Cost Location Notes
Materials IOC 1 Coated Optics Lens Clens #1 $100 for 1 qt Online The pink liquid
IOC 2 Optical Mirrors Lens Clens #2 $100 for 1 qt Online The yellow liquid
Edmund Lens Tissue EO Lens Tissue Commercial $11 Online Yellow paper

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:

Laser Maintenance Log Sheet