Welcome to Our Community

Some features disabled for guests. Register Today.

My 1st C-Beam CNC

Discussion in 'CNC Mills/Routers' started by mikework, Oct 9, 2017.

  1. mikework

    mikework Well-Known
    Builder

    Joined:
    Jul 19, 2017
    Messages:
    11
    Likes Received:
    7
  2. mikework

    mikework Well-Known
    Builder

    Joined:
    Jul 19, 2017
    Messages:
    11
    Likes Received:
    7
    I am really looking forward to any feedback during this.

    Right now I am thinking of cutting the 4th c-beam into 2 375mm legs for the gantry and 250mm for the z-axis c-beam.

    I guess if that is too short for a 1.5kw spindle on the Z axis I can always replace just that piece.

    Any thoughts folks?
     
  3. mikework

    mikework Well-Known
    Builder

    Joined:
    Jul 19, 2017
    Messages:
    11
    Likes Received:
    7
    Got some more work done over holidays. Its not bolted down yet as I want to get some electronics installed and test the motion before locking it to a surface. As is, its very rigid.

    All aluminum plates cut and drilled by hand. I can not wait to be able to machine these instead by hand as tolerances HAS to be waaaay better.

    Also discovered I had to improve my tablesaw 90 degree cuts of the c beam ends as I was getting some serious motor shaft to leadscrew misalignment.

    Thanks to William Ng's '5 cut method' for tablesaw crosscut sled alignment the c-beam ends are now within .9991% tolerance of 90 degrees.

    Z plate was sized for 2.2kw spindle which will be one of the last upgrades. I have a beater router I can test with for now.

    4 Thread 8mm leadscrews are used for y and x, but I will stay with the 2 thread 8mm to help the 275oz stepper motor haul that 5 kg 2.2kw spindle up and down. Other axis are using 425oz steppers.

    Finding a source for lock collars locally was ridiculous so I drilled out some standard nuts and added 2 60 degree offset setscrews.

    Stepper motor spacers came from electronics spacers stash. Wide variety of lengths employed.

    'Y' / Gantry support plates cut wider for extra stability. I may add more wheels to all plates based on performance.

    V Slot calculation spreadsheet indicates a total .06 mm deflection (total weight 11.5kg with spindle) in side c-beams so I may go to a 2 sided support Y plate 'sandwich' instead of supporting the beam in the middle.

    Waiting now for a Arduino Uno to install GRBL on to. This will run the 4 DM542 drivers for each stepper.

    Sorry for lower picture resolution, main camera has hidden charger over holidays.

    PHOTO_20180112_093222.jpg PHOTO_20180112_093320.jpg PHOTO_20180112_093514.jpg PHOTO_20180112_093533.jpg
     
    #3 mikework, Jan 12, 2018
    Last edited: Jan 12, 2018
    jamesdjadams likes this.
  4. GrayUK

    GrayUK The Secret of Life is ..... Choice!
    Staff Member Moderator Builder

    Joined:
    May 5, 2014
    Messages:
    1,304
    Likes Received:
    407
    Just a thought. :rolleyes: Seeing as how you have a little room left at the top of your towers, why not strap a piece across the top of them, with a plate and some wheels attached to the Z axis, to act as a brace for the Z axis and remove the chance of a pivot point, or router/spindle nodding. :thumbsup:
    Gray
     
  5. mikework

    mikework Well-Known
    Builder

    Joined:
    Jul 19, 2017
    Messages:
    11
    Likes Received:
    7
    Very good point.

    Might as well, the 'towers' were left tall to allow me to change the Z depth depending on stock or project needs.

    IF there was a need. I am very much still in 'Discovery' mode.

    It will have to wait till I get more aluminum extrusion. A 20x80 piece oriented facing down should do the trick nicely.

    Thank you for the great observation!
     
    GrayUK likes this.

Share This Page

  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.
    Dismiss Notice