1. #1
    Hi all,
    In the latest design for the troublesom Y axis for my plasma table i am using two 25mm end supported round rails, one above the other for the Z axis to locate to, but with a strech of 1500mm I wonder if i'm asking a bit much of them,of course it all depends on the weight of the Z axis 5 or 6 kg sound ballpark? The other consideration being the depth of pocket v length of arm.
    Any sugestions/opinions welcome.


  2. #2
    6kg at the centre of 2off dia 25mm rails of 1500mm length is about 0.5mm sag (at the centre of the span). Fairly easy to calculate.

    The question then is how important is this amount of Z sag for a plasma? How critical is the variation of distance to the workpiece when cutting?

    Also, if the load is offset then the rails will twist. This will rotate the plasma away from 90deg to the material. Again, how important would it be if the cut angle was a few degrees out? I suspect the problem would be a slight chamfer on the edge of the workpiece.

    I'm sure some Plasma expert can help you out with these further questions.
    Last edited by routercnc; 23-09-2010 at 11:43 AM.
    Building a CNC machine to make a better one since 2010 . . .
    MK1 (1st photo), MK2, MK3, MK4

  3. #3
    Thanks, Z sag i don't like the sound of, but the torch hight control would take care of that?. Twisting is something else though, can't have that! i'll have to think again.

  4. #4
    Couldn't you avoid any twisting by balancing the Y axis....i.e. put a suitable mass the other side of the rails to the plasma torch so that the centre of mass falls directly between the two rails. Admittedly that's going to make it even heavier, but still if twisting is worse than sagging then that's ok...

Similar Threads

  1. Mach 4 Demo Released Today (Looksy only NO Motion)
    By JAZZCNC in forum Artsoft Mach
    Replies: 10
    Last Post: 24-04-2014, 10:34 PM
  2. VFD went pop today
    By Washout in forum Spindles & Drive Motors
    Replies: 4
    Last Post: 09-03-2014, 09:29 PM
  3. NEW MEMBER: Hi All new today a world of information here great site
    By millmateuk in forum New Member Introductions
    Replies: 0
    Last Post: 20-11-2012, 12:03 AM
  4. NEW MEMBER: Goal - Enable 3-Axis CNC Bed Mill to Perform 5-Axis Milling
    By LoveLearn in forum New Member Introductions
    Replies: 2
    Last Post: 25-01-2012, 07:46 PM
  5. Precision metal processing (3 axis, 5 axis, 7 axis) OEM
    By 7AxisCNC in forum Manufacturer News
    Replies: 0
    Last Post: 17-05-2011, 01:04 PM


Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts