Home built CNC table

The problem is that most decent xyz-tables start at $10,000. I have a
reasonable amount of disposible income (what with inflation we're all
millionaires) but I challenged myself to get something at 10% of the
cost. I treated the project as "how would most modelers be able to cut
balsa for under $1500?".

I built my own CNC table starting from hardware from these guys:
http://www.servosystems.com/lps_page1.htm I paid $700 and I
did a major rebuild of the configuration to get the z-axis.



Sorry, I know the picture doesnt show a lot of information. The format
it cuts is 6 X 12 inches. To buzz larger sheets I use 6 X 36 inch
lengths and lay the whole sheet on the table and cut one side at a
time. The table cuts 1/16th inch ply, and 1/4 inch thick balsa. The
router on the table almost certainly is capable of cutting much
thicker wood.

Tables are one thing, but hhat most parties will find challenging is
not so much the machine but the motor drivers/power supply/computer
interfaces. You can buy drivers relatively complete packages:
http://www.microkinetics.com/
http://www.flashcutcnc.com/index.html
http://www.mendonet.com/cnclinks/ 
http://www.maxnc.com/ 

No one seems happy with MAXNC10 drivers.

http://www.super-tech.com/ 

(also has complete tables)

But I had some existing equipment so I just needed motor drivers. For
this I bought drivers from: http://www.cyberpakco.com/cy41.htm

Remember you'll also need power supplies (yes, more than one) and
cooling fans and it helps if its all built into a sturdy box that you
can stand on when trying to pull fowled up parts out of the table.

The power supplies you'll need are to get major amperage to the
motors, and nice lightweight power to the logic circuits that go
between the parallel port of the computer and the drivers.  If you're
not prepared to get into the electronics, or if you cant buy a
pre-packaged system, home CNC balsa cutting is not for you.

Avoid thinking that you can do this with dot matrix printer
parts. These will not going to create a lot of lateral force and I
think its unlikely that you'd be able to make parts with much
precision. However, the combination of printer parts with highspeed
pneumatic tools has a good chance of working because the
low-frictioncutting between tool and wood.

Typical ebay searches that will start you looking at used equipment:
x-y table
CNC table
stepper motor

The results from these searches will always differ but I'm looking at
some pretty good deals right now. As any ebay user is aware, it is not
uncommon for bidding to exceed the actual value of the item so please
be careful.

There are also some very competitive system on ebay that come under
the category engravers -- they do the same thing after some minor
modifications.