marco_c

Forum Replies Created

Viewing 6 posts - 1 through 6 (of 6 total)
  • Author
    Posts
  • April 4, 2015 at 2:08 am in reply to: Y axis motors stopped working #7594
    marco_c
    Member

    SPJS version is the latest 1.80.

    I have solved the problem. It turns out there was a broken wire between the back of PC box and the motor. I decided question my assumptions about what was going on and wired one of the new motors directly to the TinyG – it worked flawlessly! I then checked the continuity of the wires between the back of the TinyG and the motor and one of the cores for the motor control, BUT, when the carriage was in the furthest position the break was ok and the motor signals got through (hence why it was working and the failing during the traverse. It also explains why both motors misbehaved (same cable) and why the problem remained with the axis no matter which motor controller was selected in software.

    Replaced the cable with the intermittent core and it all works fine now. It looks like there are no bugs in the code after all 🙂

    Thanks very much for your responsiveness, support and patience – great to be part of the community.

    April 3, 2015 at 12:03 am in reply to: Y axis motors stopped working #7587
    marco_c
    Member

    Tried a few more things:
    1. Moved the USB port to another one on the computer and changed over the cable. No change.
    2. Put back the original motor instead of the replacement, but only connected one of the Y axis motors. No change, still stutters.
    3. Tested the motor driver chips to see if they were getting excessively hot. All felt just warm to the touch. The hottest was Motor 1 (X Axis) and it was no problem keeping my finger on the chip indefinitely (ie, it really was not excessively hot in any way).

    I measured the voltage as you suggested but it seems to stay at 24V or close to it.

    I made a video with commentary of the setup, the problem occurring and took a dump of the TinyG configuration – see this https://www.dropbox.com/sh/sga69j2wq7jt74x/AAAmcM0R0ZG3EjL0D4yXGsfGa?dl=0.

    April 1, 2015 at 12:21 am in reply to: Y axis motors stopped working #7580
    marco_c
    Member

    It has been a while but I have now had time to play a bit more, including replacing one of the Y axis motors to see if it makes a difference. It makes no difference – the motors work in the extreme sections of the linear travel but ‘stall’ in the middle. Instead of spinning in a specific direction, the motor appears to spin a fraction one direction then a fraction in the other. This creates a jitter but does not move the assembly anywhere.

    At the end of the section where it moves freely, the TinyG resets. This stops the motion dead, clearly. The jittering is also stopped when the TinyG resets itself (flashing red LED). Tried changing USB cable (one the basis of Rural’s post and resolution) but it makes no difference.

    What puzzles me is that it works for the end sections of travel (near home and at the other end) but not for the 70% rest of the span. Any more ideas? I am about ready to tear out the little hair I have left!

    • This reply was modified 9 years, 5 months ago by marco_c. Reason: Additional information
    March 14, 2015 at 8:37 pm in reply to: Y axis motors stopped working #7542
    marco_c
    Member

    Been busy with other things but finally got back to this today. Updated the firmware to 440.14 using TinyG-Updater and running SPJS 1.80. Tried the following:

    1. As I have 2 motors on the Y axis, I disconnected each in turn to see if it made a difference, ‘jogging’ 100mm at a time to see if the problem was isolated to one motor only. Both motors did the same (grinding/stuttering in a section of the travel, smooth past that point).

    2. In software, swapped X and Y axis motor controllers and the problem stayed with the Y axis. I guess from this it is probably not the controller but in the wiring/motors. Is this a valid conclusion?

    3. I did notice that frequently, moving the Y axis would cause the TinyG to reset when it went from the ‘smooth’ section of travel to the ‘stutter’ phase. Not sure what this means, but it might help.

    I am ordering 2 spare steppers to try out, but in the meantime does this info help to diagnose this any further?

    Thanks.

    March 3, 2015 at 10:12 pm in reply to: Y axis motors stopped working #7499
    marco_c
    Member

    I have now updated the firmware to 440.13 and had to redo the config parameters (a warning about this would be useful in the firmware downloader!).

    Still no joy with the Y axis movement. What I have noticed is that the motor ‘grinds’ and if I help it in the direction it is supposed to be going, it eventually starts moving smoothly on its own, once it is past a certain position on the axis). Is it possible that one (or more) of the coils in the motor are damaged? Any hints as to how I could determine that to be the case?

    Can you also confirm if the G28.2 command has been changed so that all 3 axes are supposed to move together? I had that occur once withe the new software but this was not the case with previous firmware.

    February 27, 2015 at 12:58 am in reply to: Y axis motors stopped working #7475
    marco_c
    Member

    Firmware is 435.1, so it is a little out of date but not much. The board was purchased late last year (2014).

    One of the options for setting up the dual motors is to wire them up to the same motor control. I wanted to keep one axis free in case I decided to implement a fourth rotation axis as well. As these are NEMA17 motors there should be no problem with the current. And, as I said before, the motors worked fine and the pot setting is at about half full range.

    • This reply was modified 9 years, 6 months ago by marco_c.
  • Author
    Posts
Viewing 6 posts - 1 through 6 (of 6 total)