A CNC Repair

Discussion in 'General Electronics Chat' started by R!f@@, Nov 4, 2014.

  1. R!f@@

    Thread Starter AAC Fanatic!

    Apr 2, 2009
    Hey Guys.
    Been a while I posted something interesting.
    Been busy more than a bit.

    I like to share a new experience I had with a CNC Engraver.


    This one was brand new. Owner bought from China and shipped via DHL and cost a lot. Well more than I can buy one.
    Problem was he can never get this to run. No matter what. All it does is spindle motor run. Obviously it was controlled manually. So motor Runs. Other than it was useless. He came to me when he ran out of options.

    So I checked. The software does not run, meaning no change in axis control. Owner tried with Win7 and XP and all tht.

    I found two problems after banging my head for two days. A DC to DC controller on the PCB was dead plus the Y axis IC. Good thing I bought those to build my CNC.

    The DC to DC controller was one thing I cannot get here, so I compromised. I added an extra winding to the Tx ( good thing it was a toroid ). Made a 7805 regulator and replaced the IC.
    Re installed win7 and Mach 3 and studied the LPT pin out on PCB. Had to change the Reset pin. And bingo it started to work.



    Managed to to do a sample from the installation CD


    But I had to admit building a CNC is one thing. And to Engrave is another whole ball game.
    Still learning how to Engrave and do proper tool path. This is tough.

    Managed to destroy a sample tool bit... forgot to start the spindle.

    And still learning the Drawing Software.....Man this is not the same as repairing a CNC !!!!

    PS. I always thought drawing and sending to CNC was the easiest part As like draw in corel and sent to printer. I was dumber than I thought. Eh!
  2. Dr.killjoy

    Well-Known Member

    Apr 28, 2013
    Awesome job !!!!
    I would have just replaced the main board and be done with it..
  3. R!f@@

    Thread Starter AAC Fanatic!

    Apr 2, 2009
    Replacing means getting the board from China and it takes a month or so. Besides owner was chatting with the seller for days with no luck.

    By the way this was the very first time I get to lay my hands on an Engraver you know, so I cannot let it go without studying the thing.
    It was well worth it.
  4. MaxHeadRoom


    Jul 18, 2013
    What front end software is it Mach or ?
    If you have both CAD and CAM program or a combined one it is usually not that bad, depends on what you are using.
  5. nerdegutta


    Dec 15, 2009
    Great work, R!f@@ !!

    I used LinuxCNC on my homemade CNC machine.
    R!f@@ likes this.
  6. R!f@@

    Thread Starter AAC Fanatic!

    Apr 2, 2009
    I was fiddling with Vectric (now)
    Before Lazycam (crazy software), then Corel to DXF to Lazycam and to Mach3.(too long)

    Vectric is awesome
  7. mcgyvr

    AAC Fanatic!

    Oct 15, 2009
    For my homemade CNC machine..
    I use Autodesk Inventor to design the parts (3d modeling) and the free HSM express CAM add-in for it to generate the g-code
    Makes it SOOOO easy.