Sometime in the 80's I purchased an EIA 430 Dataplotter from Government
Surplus in Ottawa. The plotting area was 31" x 36" and 64" by 50"
overall. It weighed 300 lbs but also came with a Control Console
weighing 400 lbs. The latter also included a 1/2" tape
unit. I'd retired before I started turning it into a CNC unit,
helped along by a 2007 book of CNC Router
Plans by David Steele . From this I basically built the Z-axis
and router head
because the X and Y-axes really just needed steppers and threaded rod.
(Home Hardware)INTERFACE
The interface is built into an old PC chassis using the Drive Bay to hold two PC power supply cards. These have their 12 volt lines wired in series to give me 24V for the stepper motors. I probably need more volts (it's on the list). My interface card and drivers are from Phil at pminmo. I originally etched four PCBs from his notes but my copper work and soldering weren't the best and only two are still in-place the others being replaced from blank boards that Phil sold. The interface card takes the serial port from the PC and drives up to four motor controllers along with a handful of I/O lines for Emegency Stop, All Home etc. Two relays from old Microwave Ovens are used to run the Spindle and power a vacuum unit ( also on the list) One remote line is used to turn on an Extraction Fan (in the next room!)
I've also added a Super-PID Spindle Speed Control all the way from sunny Australia. I really should be making more of this stuff but I'm running out of time!
The limits and homing units use microswitches also salvaged from old Microwave Ovens.
CONTROLLER
The controller is another old PC running Ubuntu Linux 10.04 LTS. I've added a parallel port ABC box on the back so I can switch from the Interface to a small Driver Test unit. This PC might have problems with the graphics card as it shows signs of getting very slow which isn't good for CNC.
SOFTWARE
I'm running LinuxCNC as the G-code interpreter although it can also generate G-code using the maths package. You'll see in some of my code the item doesn't exist as a drawing, just a series of parameters followed by a number crunch. I have also used COREL Draw and the like to design some 2D items/text and then run dxf2gcode to create the g-code.
PROJECTS
- GEAR PUMP
- GEARS
- DRILL PATTERNS IN ASCII
- POLICE BOX
- CRIBBAGE BOARD - TURKEY
- CRIBBAGE BOARD - FLATBED
- CRIBBAGE BOARD - BOAT
- CURTAIN COG
- MORTICE AND TENON
- HOCKEY STICK - DESIGN
- BUCKYBALL - Buckminsterfullerene - Truncated Icosahedron ...