Need Help! Mach3 - BOB - Loosing steps


Page 1 of 2 12 LastLast
Results 1 to 12 of 22

Thread: Mach3 - BOB - Loosing steps

  1. #1
    Registered
    Join Date
    Jan 2016
    Posts
    13
    Downloads
    0
    Uploads
    0

    Default Mach3 - BOB - Loosing steps

    I'm in the process of building my first machine with Mach and a Parallel port. I built one other machine running grbl. I have a issue with loosing steps on one of my dual x axis motors, so i wanted to take a look at the signal going to the drivers.




    Notice the missed pulses..and the noise.. I can tell that both axis are missing steps, but i dont really have a good way to compare that one has x more than the other. (i wonder if the arduino interrupts would be fast enough to sample the pulses)

    Im using the amazon special SainSmart BOB


    I also looked a bit closer and found that they were not in sync. Not out by too much about 1.5us but im not sure how close they should be either.



    So fellow CNC'er i ask you all for advice, what should i be looking at next, could it be a BOB issue, PC issue... Should i just bite the bullet and buy a smooth stepper board?

    Mods, i looked for a troubleshooting thread but came up empty handed, if this needs to be moved, please do so.

    Similar Threads:


  2. #2
    Community Moderator ger21's Avatar
    Join Date
    Mar 2003
    Location
    United States
    Posts
    30048
    Downloads
    0
    Uploads
    0

    Default Re: Mach3 - BOB - Loosing steps

    First thing to do is run drivertest.exe from the Mach3 folder. Disregard the "System Excellent" message if you see it. What you're looking for is a smooth, flat line, and a steady pulse rate.

    Gerry

    UCCNC 2017 Screenset
    http://www.thecncwoodworker.com/2017.html

    Mach3 2010 Screenset
    http://www.thecncwoodworker.com/2010.html

    JointCAM - CNC Dovetails & Box Joints
    http://www.g-forcecnc.com/jointcam.html

    (Note: The opinions expressed in this post are my own and are not necessarily those of CNCzone and its management)


  3. #3
    Registered
    Join Date
    Jan 2016
    Posts
    13
    Downloads
    0
    Uploads
    0

    Default Re: Mach3 - BOB - Loosing steps

    Ok, Next steps today, i did run the driver test file, however it wasn't very intuitive what i should be seeing.


    I took the parallel cable loose from the PC and probed it directly, same missing steps. No noise however.





  4. #4
    Community Moderator ger21's Avatar
    Join Date
    Mar 2003
    Location
    United States
    Posts
    30048
    Downloads
    0
    Uploads
    0

    Default Re: Mach3 - BOB - Loosing steps

    Watch the pulses/second at the top, and see how steady it is.
    And the graph should be a single horizontal line, not like yours. While your isn't ideal, I'm not sure that it's the cause of your problems.

    What do you have your pulse widths set in motor tuning?

    Gerry

    UCCNC 2017 Screenset
    http://www.thecncwoodworker.com/2017.html

    Mach3 2010 Screenset
    http://www.thecncwoodworker.com/2010.html

    JointCAM - CNC Dovetails & Box Joints
    http://www.g-forcecnc.com/jointcam.html

    (Note: The opinions expressed in this post are my own and are not necessarily those of CNCzone and its management)


  5. #5
    Registered
    Join Date
    Jan 2016
    Posts
    13
    Downloads
    0
    Uploads
    0

    Default Re: Mach3 - BOB - Loosing steps

    I tried 0 an 5 us. ... Gave up.. ordered a ESS... Should solve my issues..



  6. #6
    Registered propellanttech's Avatar
    Join Date
    Sep 2011
    Location
    United States
    Posts
    54
    Downloads
    0
    Uploads
    0

    Default Re: Mach3 - BOB - Loosing steps

    What operating system???



  7. #7
    Registered
    Join Date
    Jan 2016
    Posts
    13
    Downloads
    0
    Uploads
    0

    Default Re: Mach3 - BOB - Loosing steps

    Quote Originally Posted by propellanttech View Post
    What operating system???
    XP sp3 x32



  8. #8
    Registered propellanttech's Avatar
    Join Date
    Sep 2011
    Location
    United States
    Posts
    54
    Downloads
    0
    Uploads
    0

    Default Re: Mach3 - BOB - Loosing steps

    Let me explain why I asked;

    Any Windows operating system after 98 doesn't give the parallel port priority with relation to time. Hence why many systems have moved away from the parallel port. The pulses can be interrupted by anything Windows deems more important, hence lost pulses. You do not have this problem is running Linux, or other operating systems.

    This may not be the problem, but be very careful to not let a screen saver or any other program run while using Mach 3. You should have no screen saver, and the power options should be set where everything stays on except possibly turning of the monitor feed, which lets the monitor power down to a sleep state.

    Your mileage may vary.

    James L



  9. #9
    Registered
    Join Date
    Jan 2016
    Posts
    13
    Downloads
    0
    Uploads
    0

    Default Re: Mach3 - BOB - Loosing steps

    Yeah, Windows isnt a RTOS, so im not surprised to have this issue, What i was surprised to see was that the data streams were not in sync. I would think the computer (its like a 2+ghz machine) could fire the interrupts to generate the pulses more accurately than 1.5us. I tried almost every setting i could find referenced to enable "high power, etc". It was so bad just jogging the machine around with the keyboard would cause my gantry to become unsquare. Hopefully this ESS will fix my issues, and now i can actually put a more modern PC on this machine.



  10. #10
    Registered
    Join Date
    Dec 2004
    Location
    USA
    Posts
    56
    Downloads
    0
    Uploads
    0

    Default Re: Mach3 - BOB - Loosing steps

    Quote Originally Posted by propellanttech View Post
    ~
    You do not have this problem is running Linux, or other operating systems.
    ~

    James L
    Disagree! Using the same computer (dual booting from separate SSDs in BIOS) and PP, Mach3 under Windows 7 outperforms LCNC under Debian Linux. And the latter is using a kernel with RT extensions geared towards LCNC use. I'm able to get the maximum PP step rate of 100KHz indefinitely with Mach3 but limited to 60KHz with LCNC. Granted, a certain amount of savvy is required in order to get Windows to perform this way, but the same applies to Linux.

    Last edited by eldata; 08-11-2017 at 06:37 PM.


  11. #11
    Registered propellanttech's Avatar
    Join Date
    Sep 2011
    Location
    United States
    Posts
    54
    Downloads
    0
    Uploads
    0

    Default Re: Mach3 - BOB - Loosing steps

    Quote Originally Posted by eldata View Post
    Disagree!. Using the same computer (dual booting from separate SSDs in BIOS) and PP, Mach3 under Windows 7 outperforms LCNC under Debian Linux. And the latter is using a kernel with RT extensions geared towards LCNC use. I'm able to get the maximum PP step rate of 100KHz indefinitely with Mach3 but limited to 60KHz with LCNC. Granted, a certain amount of savvy is required in order to get Windows to perform this way, but the same applies to Linux.
    I stand corrected.....I'll stick to ethernet connections.

    Thanks for the education,

    James L



  12. #12
    Community Moderator ger21's Avatar
    Join Date
    Mar 2003
    Location
    United States
    Posts
    30048
    Downloads
    0
    Uploads
    0

    Default Re: Mach3 - BOB - Loosing steps

    Mach3 performance is very much tied to the specific PC. Some PC's run mach3 very well, and some can't run Mach3 at all.

    Gerry

    UCCNC 2017 Screenset
    http://www.thecncwoodworker.com/2017.html

    Mach3 2010 Screenset
    http://www.thecncwoodworker.com/2010.html

    JointCAM - CNC Dovetails & Box Joints
    http://www.g-forcecnc.com/jointcam.html

    (Note: The opinions expressed in this post are my own and are not necessarily those of CNCzone and its management)


Page 1 of 2 12 LastLast

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
  •  


About CNCzone.com

    We are the largest and most active discussion forum for manufacturing industry. The site is 100% free to join and use, so join today!

Follow us on


Our Brands

Mach3 - BOB - Loosing steps
Mach3 - BOB - Loosing steps