DIY CNC Acrylic Cutting

Yesterday Becky and I went to Ricks with a bunch of the guys and he taught us the basics on how to work acrylic.   I really learned a lot, and I wanted to return the favor.   Rick says he's interested in obtaining a CNC machine that will allow him to cut more sophisticated shapes, but the price tag on such a machine new is about $10K.  I'm experienced at working with electronics, so I offered to the electronics for a CNC machine if he would do the mechanics.
Here are some great instructables:
This guy built a large gantry and uses it to cut foam:
http://www.instructables.com/id/How-to-Make-a-Three-Axis-CNC-Machine-Cheaply-and-/
This guy built a very small gantry (Table Size) and uses it to engrave circuit boards:
http://www.instructables.com/id/Easy-to-Build-Desk-Top-3-Axis-CNC-Milling-Machine/
The second guy also designed his own control circuit (Way to much work when one can be bought for $60 )
The basic idea is you build a 3 axis computer controllable gantry, plug it into your computer, and the computer does all the hard work.   You can download open source software that will take drawings from software like autocad and corel draw and convert them into step and directional signals suitable to drive the gantry.    The gantry carries whatever kind of tooling you want to load into it.    For acrylic a router would be good, and a laser would be better.
All in all, sounds like a $600-$700 project.   The electronics and motors will run about $300.
David

 

Yea, honestly it's amazing what the commercial guys manage to get people to pay for 3 stepper motors, a $60 controller, a few big screws and a table.