V90

V90 Milling Machine

• The bed is 12" x 18". The cutting area is 11" x 17".
• Vertical travel (z-axis) is 3 inches minus the length of the cutter
• Takes G code only.
  • pycam works well to convert an STL model to G code for the V90
  • If only drilling holes these online tools work well
  • Skeinforge (also possibly used for 3D printing) can be setup for milling. (Also takes STL)
  • Other software packages can be used as well. (MeshCAM (non-free) is one that's been used in the past.)
• To start the software, click on "V90 router" at the bottom
• Takes 1/8" shanks. You can buy bits at Precise Bits
  • Small bits are easy to break. Keep this in mind if using any small endmills/drills, and when changing bits. (A bump from one of the wrenches can ruin a bit.)
• When installing a bit, there is a coned spacer/collet. The narrow part of the cone goes up, with the wide part at the bottom.
• There are limit switches to stop the machine from damaging itself if it goes out of bounds.
  • The limit switches are in series so if one is tripped, the machine will stop and not know which one tripped it.
  • If a limit switch is tripped, disable the stepper motors then move the stepper motor shaft until the switch is no longer tripped.
• There is an Emergency-Stop located to the right of the screen. This stops movement, but does not turn off the router.
  • The machine will keep coordinates, and as such, can be restarted from the E-Stop if needed.
• For the G code, the cutting motor control doesn't do anything. Turn the motor on and off with the hardware switch and adjust its speed with the speed controller knob inside the machine. (Gcodes: M3, M4, M5)
• Warning: DO NOT cut power to the whole machine before cutting power to the stepper motors.
  • This is a speculation as to what burned out a stepper motor controller, and unfortunately these aren't cheap pololu drivers.
• Warning: The stepper motors will get quite hot in operation. Touch them at your own risk.

handy G-Code to know

• G20 - Units are in inches
• G21 - Units are in millimeters
• G00 - move fast (position to new area as fast as allowed by the machine, NOT for cutting! When using this, your Z-Axis needs to be high enough to avoid the risk of cutting.)
• G01 - Linear move slow (cutting, will move in a straight line at the feed rate.)
• G90 - Absolute coordinates, default (G1 X1 will then move to X = 1 unit (dependent on G20/G21 above))
• G91 - Relative coordinates (G1 X1 will then move to X = X + 1 unit (dependent on G20/G21 above))

Additional information on g-code and m-codes (Generally just known as G-Code)

• Quick reference showing both (not all codes supported): http://linuxcnc.org/docs/html/gcode.html
• Mach3 (the software the V90 uses) reference: http://machmotion.com/cnc-info/g-code.html
• Mach3 (M-codes) http://machmotion.com/cnc-info/m-codes.html/

Materials

• Wood
• Plastic
• Acrylic
• Some metals, including Aluminum.
  • Be very careful cutting metals. It is strongly recommend to ask for help before trying to cut any metal.
  • Do not try it with any harder metals (Steel especially). The frame is not up to it.
  • Aluminum is tricky, start carefully with a low feed rate. (Note: I'll see about finding the values for aluminum, please post a message on the list if you need them before I update this again. - James L.)
  • If cutting aluminum, make sure that collet is very secure, and watch it. If it is not, it can dig into the material and come lose then dig in or potentially throw the bit out with a dangerous amount of energy.