CNC / CAM Milling machines

Home Built?

• use 3 old dot matrix printers carriages for the mechanics?
• Hardware store drawer slides, skate bearings on pipe/rod/angle, threaded rod, stepper motors, laminate router. The big advantage here is that it can all be cut, filed, and bolted together with little more than hand tools.
  • http://www.cnczone.com/forums/showpost.php?p=102542&postcount=270

Conversions?

• BillW says:

  But aren't there a fair number of CNC-convertable mini-mills in about that price range? harborfreight has
  http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=39743 for about $400. and while the cheap chinese tools have a mixed reputation, they're probably a better starting point than scratch

• http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=47158 $300
  http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=3135 2.5"x2.5" sliding table.

Problems:

• Backlash Must be eliminated in hardware. Backlash compinsation is not applicable in Mills.

  Peter Van Hoof says: "You set up your x-y table in front of the milling bit lined up exactly where you want it the bit turns as seen from above clockwise (just like an electric drill) the last adjustment to line the piece to be milled you moved it a little to the left you now move the piece forward against the bit the spinning bit excerts a force to the left on the piece being milled and because the backlash is left at the wrong side of the piece it will jump making measurments inaccurate and potentially creating a dangerous situation."
   

• Non-Linearity

  Denny Esterline says: "Hardware store rod does have a nonliniarity problem. Rods I've measured are between -10 and +30 thou per "inch" of turns. The driver board I designed stores calibration constants in eeprom and compensates every half inch. With this method I was able to achive absolute positional accuracy of less than five thou."

Also:

• Panels@ Cases@ Mounts@ Enclosures@ Cables@
• CNC@ CAM@
  Position Sensors@ Steppers@
• Casting@
• Plexiglass@, Metals@

See also:

• http://www.fignoggle.com/plans/cncplans.htm This site has a lot of information on the Sieg X2 mini mill CNC conversion. CNC Conversion Plans and DRO Plans available. Lots of information updated daily.
   
• http://www.hobbycnc.com/ CNC Hobby Router Plans
   
• http://www.duncanamps.co.uk/metal/cnc_mill.htm Duncans mini-mill CNC conversion
   
• http://www.buildyouridea.com/cnc.html The: IG-88. Just a lovely machine
   
• http://www.milinst.com/robotics/robotics.htm#axis More for drilling than milling
   
• http://www.kleinbauer.com/ Several designs for low cost machines. Don't ask questions, just pay for the plans. JCK has indicated many times that he has been much maligned:
  • "This week it will be four years ago I entered CNC Hell"
  • "It bothers them that I am doing so well. While they laughed I worked. Now I am laughing at the Zoloser!"
  • "First they mock then they copy"
  • "After three years of killing myself in this hobby I come to realize some people will never link my page or even mention me in an online conference. So I have removed their links from my page. "
  • "I know what you might be thinking! He sells plans, so he is telling me to build my own machine using the plans he sells!!! If you think this is true, then you don't know shit! For every hour I put into this hobby I make ten cents! "
  • "People would drop in on my website and leave me rude messages telling me my machine was a piece of junk. I have never forgotten those Emails to this day!"

  How about making a nice donation to him to make up for it?
  http://www.crankorgan.com/order.htm
   

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