Laser Cutter

For this device an introduction is needed. Send an email to sil-ee@utwente.nl to schedule one.

On the first booking of the laser cutter, there will be a beginner introduction given by one of the lab assistants. They will guide you through some basic usage using Ruby to get you started. Remember that you should bring your own material to use in the laser cutter; a list of allowed materials can be found down below; else make sure to contact the lab assistant that is giving you the introduction.

The laser cutter available in the Systems Integrations Lab is a Trotec speedy 300; which means the bed is 735 x 435mm with a maximum material thickness of 6.5mm. Some examples of common cutting materials are acrylic (PMMA), polypropylene (PP), polyoxymethylene (POM), timber/plywood, cardboard, paper, leather and textiles.

When using the laser please remember to: 1) Not stare directly into the laser when it is operational. 2) Always remember to close the lid before starting your job 3) move the laser head away from being above your substrate if you want to take the substrate out of the machine so as not to damage the laser head. 4) if something seems to go wrong, press the stop button on the operator panel or press the emergency button on the machine and take proper measures onward.

The following is information taken from here

a) Color your lines and fills in your image according to whether you want each element cut, vector engraved, or raster engraved. The default colors are red, cyan, and black respectively, but don't worry about getting these colors precise. The important thing is that you differentiate your desired outcomes using different colors for easy group selection later in the Ruby software. Unlike with JobControl, you no longer need to meticulously set line weights for thru cuts or vector engraving prior to importing your file into Ruby. Once lines of any thickness are colored red or cyan in Ruby, the software automatically understands these lines are to be cut thru or vector engraved.

  • Ruby is set to interpret black outlines and/or fill as standard raster engraving (approximately 0.3mm deep). Deeper raster engraving depths are programmed for most materials [blue for 0.5mm depth, green for 0.7mm depth, pink for 1.0mm depth (achieved with 2 passes)]. When raster engraving, line weight will matter (thin lines engrave thin, thick lines engrave thick).
  • You can raster engrave (but not cut!) black & white or grayscale pixel images/photos, but the results are hard to predict depending on the size of the image, the material, and even the parts of the material (e.g., grain pattern in wood). Expect to need to cut a few test pieces, and have plenty of extra material at hand.
  • Unlike in JobControl, Ruby recognizes and executes any cuts within the boundary of a part before cutting and releasing that part from the sheet. There is no need to instruct the software to do this through the use of different line colors. Executing all cuts within the part boundary before releasing the part from the sheet provides for better cutting accuracy.
  • You can vector engrave lines, which is generally a lot quicker than raster engraving and is a great way to mark pieces (especially if you use a single line font line Inkscape’s Hershey Text). Vector engraving is basically a light cut into the surface. To do so set your lines to cyan.
  • By default Ruby will execute in the following order: raster engraving in order of depth (shallow first, deepest last), vector engraving, then cuts. You can change this arrangement by dragging the tasks into a different order, but this is not recommended. All raster engraving set set to execute from the bottom (near side) of the sheet to the top (far side) of the sheet by default.
Quick Reference
Laser cutter/engraver behaviour R,G,B Set up in vector file
Engraving images and gradients n/a use a Greyscale bitmap
Raster engraving (approx. 0.3mm deep) 0, 0, 0 Fill or stroke/outline of a thickness greater than 0.2 (smaller values won’t show up)
Vector engraving (shallow 'scoring', great for text/markings; much quicker than engraving) 0, 255, 255 Line weight not important
All thru cuts 255, 0, 0 Line weight not important
Deep raster engraving (approx. 0.5mm deep) 0, 255, 0 Fill or stroke/outline of a thickness greater than 0.2 (smaller values won’t show up)
Deeper raster engraving (approx. 0.7mm deep) 0, 153, 51 As per deep engrave
Still deeper raster engraving (2 passes; approx. 1.0mm deep) 0, 102, 51 As per deep engrave
All other lines (won't cut or engrave, but handy for alignment, layout, etc) Any colour but those above Line weight not important

Please note that in Ruby, a lot of things can be altered and the previous section should be taken as an initial guideline as more often than not, tweaking needs to be done due to differences in materials (e.g. one piece of the cheapest 3mm plywood does not cut the same as a more expensive 3mm one)

b) Convert all your items to plain vectors (e.g., text and circle/rectangle/polygon shapes into plain vectors, to give yourself the best chance at a smooth import process.

  Inkscape: Path>Object to Path
  Adobe Illustrator: Type > Create Outlines

c) Combine all your lines/shapes of each color into a single shape

  Inkscape: Path>Combine
  Adobe Illustrator: Object > Compound Path > Make

For those interested in learning how to use the free graphics tool Inkspace, you can click Here to follow a 1.5 hours step-by-step tutorial with videos.

There are two software options to interpret engraving and cutting, namely Ruby for beginners and Job Control for more advanced users. Tutorials/manuals for these software programs can be found here for Ruby. (For Job Control, please contact a lab assistant beforehand as it is a much more involved program than Ruby.)

Not all substrates have been tested yet, as we have only recently started, so if you are unsure, please send a mail to the lab assistant. If you have tested a material for some thickness that is listed here, or if anything is not listed, please be sure to contact the lab assistants as well! (Note that for most of this list, we are taking This laser cutter as a reference, taking into account our less powerful laser cutter).

Allowed Material Max Thickness tested Notes WARNINGS!
Many woods 6.5mm no Avoid oily/resinous woods Oily/resinous woods may catch fire
Plywood/triplex/Composite woods 6.5mm yes Contain glue; sometimes uneven engraving due to glue -
Paper, card stock 0.3mm yes Cuts well & very fast -
(Corrugated) Cardboard 6.5mm no Cuts well but may catch fire for high power output please ask lab assistant for help
Cork 6.5mm no Cuts well; quality of cut depends on the quality/thickness of cork. Engineered cork may not cut as well Avoid thickness (>1 cm)
Acrylic/Lucite/Plexiglas/PMMA 6.5mm yes Cuts extremely well; leaves polished edge; thicker material = bigger error & more chance of melting/fire Avoid thickness (>1 cm)
Thin Polycarbonate Sheeting 1mm yes Can be cut, but discolors badly. (<0.5mm) may cut with discolored edges; absorbs IR strongly, so poor material to use Smoke generation
Delrin (POM) 3mm no Comes in a number of shore strengths (hardness); harder tends to work better High risk of fire & formaldehyde gas; only thinner sheets allowed
Kapton tape (Polyimide) 0.3mm yes Works well, in thin sheets and strips like tape -
Mylar 1mm no Works well if it’s thin. Thick mylar has a tendency to warp, bubble, and curl Gold coated mylar does not work
Cloth/felt/hemp/cotton - no Cut well No plastic coated or impregnated cloth
Leather/Suede thin no Leather is very hard to cut, but engraving is easily done Real leather only; no imitation leather
NON-CHLORINE-containing rubber 6mm no not tested, but should be fine for cutting Beware chlorine-containing rubber as cutting causes toxic vapor
Teflon (PTFE) 1mm no Cuts OK in thin sheets -
Carbon fiber mats/weave w/o epoxy 1mm no not tested, but can be cut; is presumably very slow Coated carbon fiber can't be cut
WE-TGF thermal filler pad 1mm yes Charcoal substance when cutting; very small (<1mm) sections between cuts are possible, but look melted -
Material Risk Cause/Consequence
Solid Styrene Generates too much smoke -
MDF/Engineered woods Generates too much smoke -
PVC (Poly Vinyl Chloride)/vinyl/pleather/artificial leather Emits pure chlorine gas when cut Will ruin the optics; corrodes machine; ruins control system & dangerous fumes to you
Thick ( >1mm ) Polycarbonate/Lexan Cut very poorly, discolor, catch fire Strongly absorbs IR-radiation. Very ineffective at cutting; poor choice
ABS Emits cyanide gas and tends to melt Does not cut well; tends to melt; high chance of catching fire
HDPE/milk bottle plastic Catches fire and melts Melts
PolyStyrene Foam Catches fire The #1 material that causes laser fires
PolyPropylene Foam Catches fire Melts or catches fire
Fiberglass Emits fumes Mix of two materials that cant’ be cut (Glass and epoxy resin)
Coated Carbon Fiber Emits noxious fumes Thin carbon fiber mat can be cut - but not when coated
Polyurethane Emits noxious fumes Upon decomposition emits carbon monoxide, carbon dioxide, nitrogen oxide and/or low molecular weight hydrocarbons