Asylum Laser Cutter Usage and Safety TrainingIntroduction to Laser Cutting Derek Seabury & Jimmie Rodgers

What is this place? ●  Artisan’s Asylum, Inc. ●  Nonprofit community workshop ●  40,000+ square feet ●  Multiple craft areas ○  Welding, metalworking, woodworking, electronics, sewing, bike shop, digital fabrication and more

●  30 - 50 classes a month

Who is this guy? ● 

Who are you?

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What brings you here?

Laser Cutting Basics ● 

How a laser cutter works

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Controlling the laser cutter

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Cutting vs etching

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Air Assist

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What can be cut

How a Laser Cutter Works

How a Laser Cutter Works

How a Laser Cutter Works ●  2 stage IR laser tube −  Electricity excites He −  He excites CO2

●  One fixed mirror ●  Mirror at end of gantry ●  3rd Mirror on cart ●  Focusing lens in nozzle

Controlling a Laser ●  X-Y gantry moves the mirrors to focus energy at different points ●  Energy delivered to the material is determined by the laser power and the speed

Laser Focus ●  Focal Length is from the top of the lens to the surface of the material ●  Asylasaur has 4” lens ●  Use the Asylasaur Tool! ●  Helix focuses with an automatic touchoff

Air Assist ● 

Blows from the nozzle

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Prevents and extinguish fires

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Keeps smoke off the lens

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Alternative gases can be used to enhance cutting or suppress oxidation

Cutting vs Etching ●  Laser Cutting ○  Heated enough, material will vaporize leaving a void.

●  Laser Etching ○  At lower energy levels material will burn, melt or vaporize less than all the way through.

●  Other Lasing Operations ○  Curing, sintering, tempering...

Raster vs Vector ●  Raster graphics use an array of values for representation ○  Pixels in a picture ●  Vector graphics describe position, direction, curvature ○  From point A to point B

Raster vs Vector ● 

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Laser etching of raster images works like a dot matrix printer varying pulses across a line The Asylasaur only supports vectors (today) The Helix does rasters and vectors

Vector Graphics ●  Image files for lasercutting should be in SVG vector format ●  Vector graphics programs includes Inkscape(free), Adobe Illustrator, CorelDraw ●  Vector lines must be converted to paths to be cut or etched

Instant Inkscape ●  Importing ○  Use a bounding box for easy scaling ●  Make everything a Path ○  Path->Object to Path ●  Set Document properties ○  Default measure mM for Asylasaur ○  Portrait mode for Helix ○  Set Document size to drawing size

Instant Inkscape ●  For Asylasaur, line width(stroke) not critical ●  For Helix, set line to 0.1 mM ●  For Asylasaur, line color used to determine order of cutting- i.e. red 1st, blue 2nd, black 3rd ●  For Helix, line color determines depth of cut- red = cut, blue=engrave, black= raster

What Won't Cut ● 

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Metals − 

Require extremely high power 20x Asylasaur!

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They dissipate heat really well across material

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They are shiny and reflect the laser energy

Polycarbonate − 

Melts, smokes and catches fire. The Blackfoot will give you better results for anything over 1/16” thick

What can be Cut ●  Organics - best with one high power pass ○  Paper ○  Wood ○  Leather

●  Glass ○  Low power to avoid thermal shock

Lasercutter settings ●  Consult wiki: ●  (http://wiki.artisansasylum.com/index.php/ Asylasaur_Material_List ) for suggested settings Example:Baltic Birch Plywood, ¼”, Asylasaur Cut: 400 mm/Min,100% Etch: 1500 mM/min, 100%

What can be Cut ●  Non-chlorinated non-fluoridated plastics ○  Some cut better at high power/high speed ○  Other cut better at low power/low speed

Chlorine and Fluorine ●  Substances containing chlorine and fluorine will release them in gaseous form at high temperatures. ●  These gases will damage the coatings on the lens and mirrors by creating hydrocloric and hydrofluoric acid fumes. ●  (Also they may melt your eyes, scorch your lungs and kill you in an unpleasant manner) ●  Do not cut unknown substances!

What You Can't Cut ●  All materials must be preapproved! ○  REALLY! ●  No Vinyl ●  No PVC ●  No Moleskine – contains PVC. ●  No Polycarbonate (just not worth the stink...) ●  No cheap imported Acrylic (it probably isn't!)

You Also Can't Cut ● 

Water resistant MDF

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Pressure treated wood

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No food. Asylasaur is not food-safe!

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No food-like substances (Peeps, poptarts, etc...)

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Any unapproved materials! Check the wiki for safe materials and suppliers.

What You Can't Cut ●  All materials must be preapproved! ○  REALLY! ●  To have a new materials approved, submit a 2” x 3” sample of the material to Derek or Jimmie

Examples of Vector Art ●  Box Making: See Inkscape Box Making Extension ●  http://hackaday.com/ 2012/07/26/box-makerextension-for-inkscape/

Examples of Vector Art ●  SVG Art- Do Google Image search for SVG patterns ●  Design your own using InkScape( free), Adobe Illustrator, CorelDraw,etc. ●  See Asylum course on introduction to Inkscape for additional information

Examples of Vector Art