Laser Cutter Setup?

[SomeoneKnows]

I don't have direct access to a laser cutter but want to learn more
about getting my CAD files set up properly. I am using 2D CAD to
create templates then transfer the image to the material for drilling
and cutting locations. I'm using drill press and bandsaw to manually
create my parts. Currently I'm using an old HP LaserJet to print CAD
drawings then transferring the toner image by rubbing acetone on the
back side of the paper. This loosens the toner and allows it to stick
to the material I'm making a part from. This works fairly well on
aluminum but can cause unwanted frosting of plastic surfaces.

Can anyone suggest a tutorial on setting up CAD files to be used
directly by a laser cutter? I'm assuming it needs to be drawn in 3D to
get cutting depths for parts that are cut all the way through versus
laser etching a surface.

Also, I have access to expensive CAD systems but am developing
workshop sessions for people setting up their own home-based robotics
labs and want to find inexpensive solutions they can use. Any
suggestions on low cost CAD options you like?

[bre pettis]

Most types of cad files can be imported into corel draw and then sent to a lasercutter so you shouldnt have a problem there.

Using the transfer method, very impressive!

Bre

Bre Pettis - http://brepettis.com
Twitter - http://twitter.com/bre
Personal Blog - http:/brepettis.com/blog
Videos - http://vimeo.com/bre
Hacker Collective - http://nycresistor.com
A Universe of Things - http://thingiverse.com

[Vince Thompson]

The reason I'm asking is that I have fold lines on my CAD drawing that I would like to have a very light etching before cutting the holes and edges. Should  this be done in two passes - first the etch then a second pass to cut through? I'm guessing that I should have two files created, one for the light etch and a second for the through cuts.

Are you using corel draw for vector to raster conversion before cutting?

The acetone trick is something I learned while researching the toner transfer method of etching PCB boards. I bought the laser printer at a thrift store for a few bucks and have experimented putting a lot of materials through it to see what happens. I used that trick in a summer camp session teaching kids to build their own robots from scratch. Eleven to sixteen year old kids using an acid bath, soldering irons, drill press, and band saw for the first time - it was a lot of fun.

Vince

[Philip Steffan]

I think the digital design revolution should not depend on an odd piece of Windows software. (Actually, I was half-surprised to learn in Bre's 25C3 talk that Corel Draw, this veteran relic from the old times, still existed.)

So, we need more Open Source converters and programs (and drivers, the trickiest part I guess). Blender and Inkscape need more brothers and sisters.

Philip

[bre pettis]

cool.

with our setup you can make different colored lines have a different laser strength which will do what you want.

bre

Bre Pettis - http://brepettis.com
Twitter - http://twitter.com/bre
Personal Blog - http:/brepettis.com/blog
Videos - http://vimeo.com/bre
Hacker Collective - http://nycresistor.com
A Universe of Things - http://thingiverse.com

[Vince Thompson]

What I'm looking for is a writeup on how to specify these things in my drawing or do you use multiple drawings with a document file giving instructions on how each drawing is to be processed?

This should be something of interest to Thingiverse members too. A document like "Before You Fire The Laser"

I didn't know about the different colored lines.

Vince Thompson
Twitter - @SomeoneKnows
CCCKC Hacker Space - CCCKC
Kansas City Robotics Society - KCRS

[GlennPowers]

Check out the Gcode enabled xfig:
http://www.harbaum.org/till/cnc/index.shtml

xfig is _really_ "CAD software from the 80s"
but, it works and it's worth a try.

cheers,
glenn