584,865 active members*
5,012 visitors online*
Register for free
Login
Results 1 to 5 of 5
  1. #1
    Join Date
    Sep 2019
    Posts
    54

    Stepper gearboxes ??

    Hi I have a large esab plasma table with old servo motor and gearboxes
    If I was to convert to steppers,
    Will steppers perform better driven through gearboxes or direct drive

  2. #2
    Join Date
    Dec 2013
    Posts
    5717

    Re: Stepper gearboxes ??

    Steppers are generally best used at low speed. Normally a 2:1 reduction is OK. There is a lot more that goes into the calculation. What torque and speed is required? To use a stepper motor I would multiply the servo torque by 3 to get a starting point for the stepper required torque. But keep in mind that stepper torque drops off dramatically with increasing RPM.
    Jim Dawson
    Sandy, Oregon, USA

  3. #3
    Join Date
    Sep 2019
    Posts
    54
    Ok
    I will calculate the weight of the gantry tomorrow
    And see what gear ratio the servo gearboxes on the table are



    Quote Originally Posted by Jim Dawson View Post
    Steppers are generally best used at low speed. Normally a 2:1 reduction is OK. There is a lot more that goes into the calculation. What torque and speed is required? To use a stepper motor I would multiply the servo torque by 3 to get a starting point for the stepper required torque. But keep in mind that stepper torque drops off dramatically with increasing RPM.

  4. #4
    Join Date
    May 2015
    Posts
    684

    Re: Stepper gearboxes ??

    Steppers definitely need reduction gearing for plasma. Try and get somewhere around 1" of movement per motor revolution. Mine does about 30mm which is still ok and even down to 15mm is good too.

    If the servos are still OK, an alternative might be to retrofit with Linuxcnc and a Mesa 7i92 ethernet board and a Mesa 7i77 6 axis servo/encoder daughter card. Add to that a Mesa THCAD board for torch voltage sensing.

    Regardless of if you use steppers or servos, the Linuxcnc plasmac configuration is now without doubt the best plasma controller available on the market place for under $10k because all the THC control is so tightly integrated with the Linuxcnc motion controller and Linuxcnc's PID controllers. Having arc voltage and full access to motion control parameters lets Plasmac do things other external THC's can't even dream of. Full documentation of Plasmac is here PlasmaC User Guide
    Rod Webster
    www.vehiclemods.net.au

  5. #5
    Join Date
    Sep 2019
    Posts
    54
    Ok thankyou for the input
    Regards
    Quote Originally Posted by rodw View Post
    Steppers definitely need reduction gearing for plasma. Try and get somewhere around 1" of movement per motor revolution. Mine does about 30mm which is still ok and even down to 15mm is good too.

    If the servos are still OK, an alternative might be to retrofit with Linuxcnc and a Mesa 7i92 ethernet board and a Mesa 7i77 6 axis servo/encoder daughter card. Add to that a Mesa THCAD board for torch voltage sensing.

    Regardless of if you use steppers or servos, the Linuxcnc plasmac configuration is now without doubt the best plasma controller available on the market place for under $10k because all the THC control is so tightly integrated with the Linuxcnc motion controller and Linuxcnc's PID controllers. Having arc voltage and full access to motion control parameters lets Plasmac do things other external THC's can't even dream of. Full documentation of Plasmac is here PlasmaC User Guide

Similar Threads

  1. Servos and gearboxes and cnc tables
    By PlasmaGuy in forum Servo Motors / Drives
    Replies: 1
    Last Post: 12-10-2009, 11:43 PM
  2. Anyone know of a source for gearboxes fo the C2?
    By Claven2 in forum Mini Lathe
    Replies: 0
    Last Post: 04-15-2008, 02:34 PM
  3. Planetary Gearboxes
    By elogicca in forum Linear and Rotary Motion
    Replies: 5
    Last Post: 01-23-2007, 07:22 PM
  4. Gearboxes for Steppers
    By vacpress in forum Uncategorised MetalWorking Machines
    Replies: 1
    Last Post: 07-17-2004, 05:48 AM

Tags for this Thread

Posting Permissions

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