Blog

Lasercutting

Laser-cutting isn’t an easy job.

Before cutting you have to prepare something:

  1. Prepare your model concept
  2. prepare your work area (usually the dimension of our wood sheet are 30×60, 60×120, in 4, 6, 8 mm poplar plywood, WE DO NOT SELL MATERIALS ).
  3. use ONLY RGB colors: RED for cutting (255,0,0) or BLACK for raster engraving (0,0,0), and a special color BLUE (0,0,255) is used for vector engraving. Other colors will not be recognized properly from the machine (images can be made in degrees of gray or dithered pictures, CYMK lines will not work well).
  4. position your 2D model to waste as less surface as possible
  5. export it in a vector format (better CorelDraw native, if you really don’t have any other choice, DWG; SVGs DO NOT KEEP ALWAYS THE RIGHT SCALE!! ).
  6. come to cut!

Ps: we might be able to give you some material for the project, but it will depend on the kind of project, assignment or availability of material. Before buying any material come to talk with me.

What material can you use?

Have a look on the tables in this page to know more.

 

Safe Materials

The laser can cut or etch. The materials that the laser can cut materials like wood, paper, cork, and some kinds of plastics. Etching can be done on almost anything, wood, cardboard, aluminum, stainless steel, plastic, marble, stone, tile, and glass (most of this, only with proper coating… we don’t provide it for now).

SAFE Materials allowed:

Material Max thickness Notes WARNINGS!
Many woods 1,2cm tested Avoid oily/resinous woods Be very careful about cutting oily woods, or very resinous woods as they also may catch fire.
Plywood/triplex/Composite woods 1,2cm tested These contain glue, and may not laser cut as well as solid wood.
MDF/Engineered woods These are okay to use but may experience a higher amount of charring when cut. TOO MUCH SMOKE NOT ALLOWED ANYMORE
Paper, card stock thin Cuts very well on the laser cutter, and also very quickly.
Cardboard, carton thicker Cuts well but may catch fire. Watch for fire.
Cork not tested Cuts nicely, but the quality of the cut depends on the thickness and quality of the cork. Engineered cork has a lot of glue in it, and may not cut as well. Avoid thicker cork.
Acrylic/Lucite/Plexiglas/PMMA 1,2cm+ tested Cuts extremely well leaving a beautifully polished edge.  Thicker the material bigger the error and higher probability of melting and fire, the thinner the better.
Thin Polycarbonate Sheeting (<1mm) Very thin polycarbonate can be cut, but tends to discolor badly. Extremely thin sheets (0.5mm and less) may cut with yellowed/discolored edges. Polycarbonate absorbs IR strongly, and is a poor material to use in the laser cutter. TOO MUCH SMOKE NOT ALLOWED ANYMORE
Delrin (POM) 6mm tested Delrin comes in a number of shore strengths (hardness) and the harder Delrin tends to work better. Great for gears!  Due to the high risk of catching fire and the formaldehyde gas released, we cut only thinner sheets.
Kapton tape (Polyimide) not tested Works well, in thin sheets and strips like tape.
Mylar not tested Works well if it’s thin. Thick mylar has a tendency to warp, bubble, and curl Gold coated mylar will not work.
Solid Styrene not tested Smokes a lot when cut, but can be cut. Keep it thin.
Depron foam not tested Used a lot for hobby, RC aircraft, architectural models, and toys. 1/4″ cuts nicely, with a smooth edge. Must be constantly monitored.
Gator foam  not tested Foam core gets burned and eaten away compared to the top and bottom hard paper shell. Not a fantastic thing to cut, but it can be cut if watched.
Cloth/felt/hemp/cotton They all cut well. Not plastic coated or impregnated cloth!
Leather/Suede not tested Leather is very hard to cut. Real leather only! Not ‘pleather’ or other imitations!
Magnetic Sheet  not tested Cuts beautifully
NON-CHLORINE-containing rubber  not tested Fine for cutting. Beware chlorine-containing rubber!
Teflon (PTFE) not tested Cuts OK in thin sheets
Carbon fiber mats/weave
that has not had epoxy applied
 not tested Can be cut, very slowly. You must not cut carbon fiber that has been coated!!
Coroplast (‘corrugated plastic’) not tested Difficult because of the vertical strips. (other machines: Three passes at 80% power, 7% speed, and it will be slightly connected still at the bottom from the vertical strips)

WARNING: Because many plastics are dangerous to cut, it is important to know what kind you are planning to use. Make:zine has a How-To for identifying unknown plastics with a simple process not to be done in the DesignLab.

Materials NEVER allowed:

Material DANGER! Cause/Consequence
PVC (Poly Vinyl Chloride)/vinyl/pleather/artificial leather Emits pure chlorine gas when cut! Don’t ever cut this material as it will ruin the optics, cause the metal of the machine to corrode, and ruin the motion control system.
Thick ( >1mm ) Polycarbonate/Lexan Cut very poorly, discolor, catch fire Polycarbonate is often found as flat, sheet material. The window of the laser cutter is made of Polycarbonate because polycarbonate strongly absorbs infrared radiation! This is the frequency of light the laser cutter uses to cut materials, so it is very ineffective at cutting polycarbonate. Polycarbonate is a poor choice for laser cutting.
ABS Emits cyanide gas and tends to melt ABS does not cut well in a laser cutter. It tends to melt rather than vaporize, and has a higher chance of catching on fire and leaving behind melted gooey deposits on the vector cutting grid. It also does not engrave well (again, tends to melt).
HDPE/milk bottle plastic Catches fire and melts It melts. It gets gooey. Don’t use it.
PolyStyrene Foam Catches fire It catches fire, it melts, and only thin pieces cut. This is the #1 material that causes laser fires!!!
PolyPropylene Foam Catches fire Like PolyStyrene, it melts, catches fire, and the melted drops continue to burn and turn into rock-hard drips and pebbles.
Fiberglass Emits fumes It’s a mix of two materials that cant’ be cut. Glass (etch, no cut) and epoxy resin (fumes)
Coated Carbon Fiber Emits noxious fumes A mix of two materials. Thin carbon fiber mat can be cut, with some fraying – but not when coated.
 Polyurethane Emits noxious fumes Upon decomposition, this product emits carbon monoxide, carbon dioxide, nitrogen oxide and/or low molecular weight hydrocarbons.

Source of this information:
http://atxhackerspace.org/wiki/Laser_Cutter_Materials

Useful Links:

For students from the UT there is always the possibility of downloading for free the CorelDRAW suite.

Fonts for speed engraving.
http://www.evilmadscientist.com/2011/hershey-text-an-inkscape-extension-for-engraving-fonts/

Generic InkSkape tuttorials for lasercutting.
http://www.cutlasercut.com/resources/drawing-guidelines/styles-examples
http://www.razorlab.co.uk/need-help/getting-started/inkscape/
http://wiki.imal.org/howto/inkscape-and-lasercutter

Trace images in InkSkape.
http://blog.ponoko.com/2008/01/21/how-to-inkscape-for-ponoko-newbies-trace-an-image/

Ready made BOX Maker for lasercutting.
http://www.makercase.com/