1. Got a question or need help troubleshooting? Post to the troubleshooting forum or Search the forums!

Solved x axis missing steps/ layer shifting

Discussion in 'Troubleshooting' started by Patrick Ryan, May 30, 2017.

Page 1 of 2
  1. Patrick Ryan

    Patrick Ryan Member

    Joined:
    Aug 6, 2016
    Messages:
    83
    Likes Received:
    23
    Ok, so I've been trying to solve this problem for a while and I thing I've tried everything but I figured I would see if you guys have any suggestions. so my x axis stepper seems to be missing steps it might even seem a bit weak. so, first thing I did was check belt tension, and it still did it. Then I adjusted the driver And it still did it. I tried replacing the driver with one I had laying around (I think it was a cheap one though) still doing it. I replaced the stepper still doing it. And then finally I replaced my ramps board and it is still doing it. Not sure where to go from here, I was thinking of buying some known good quality stepper drivers and try that unless anyone has any other suggestions.
     
    #1 Patrick Ryan, May 30, 2017
  2. WheresWaldo

    WheresWaldo Volunteer ( ͠° ͟ʖ ͡°)
    Staff Member

    Joined:
    Feb 18, 2015
    Messages:
    5,905
    Likes Received:
    3,593
    Patrick, This almost sounds like an issue with heat. If the Arduino board is not cooled it doesn't work like a PC where the CPU thermally throttles just going slower, instead it will simply skip steps. Since the Arduino is under the RAMPS board there may not be enough ariflow to keep it cool. Riser feet to lift the entire printer up from the table surface will help a little. Many, including myself, have resorted to using a much larger fan to cool the RAMPS Arduino combination.
     
    #2 WheresWaldo, May 30, 2017
    Geof likes this.
  3. Patrick Ryan

    Patrick Ryan Member

    Joined:
    Aug 6, 2016
    Messages:
    83
    Likes Received:
    23
    Waldo, I have the riser feet. What size fan do you upgrade to? Do you think the arduino could have god bad causing that? That is one of the few things I haven't replaced. Haha

    Sent from my SM-G930T using Tapatalk
     
    #3 Patrick Ryan, May 30, 2017
  4. WheresWaldo

    WheresWaldo Volunteer ( ͠° ͟ʖ ͡°)
    Staff Member

    Joined:
    Feb 18, 2015
    Messages:
    5,905
    Likes Received:
    3,593
    Unless you run hot 24/7 CPUs do not degrade as fast as one might think. Your Arduino is probably fine. I enlarged the hole in the bottom and put in a slim 80 x 80 x 15 mm fan in there, found one on Amazon. 15 mm is as thick as you can go if you want to mount the fan in the same place as the original pitifully small 40 mm. Other people have added a second 40 mm that blows across both boards from the end instead of having just one blowing up onto the RAMPS.
     
    #4 WheresWaldo, May 30, 2017
    Geof and Patrick Ryan like this.
  5. Patrick Ryan

    Patrick Ryan Member

    Joined:
    Aug 6, 2016
    Messages:
    83
    Likes Received:
    23
    So, I have upgraded my ramps cooling fans to an 80mm, bought Polou black edition stepper drivers (which I calibrated according to the post in the forums), I replaced the steppers, for shits and giggles I replaced the ramps and the arduino mega and I'm still having issues with this. could this be firmware related? I'm running marlin 1.1.1 mesh. I'm not sure what else it could be.
     
    #5 Patrick Ryan, Jun 5, 2017
  6. mark tomlinson

    mark tomlinson ༼ つ ◕_ ◕ ༽つ
    Staff Member

    Joined:
    Feb 21, 2013
    Messages:
    23,912
    Likes Received:
    7,338
    I can't speak for that version of marlin as far as it relating to the issue.
    I would only say that it does not usually present as a firmware problem.

    Have you tried swapping the Axis connections to see if problem moves?
    That would either eliminate or incriminate the steppers themselves.

    How about rolling back to stock firmware (v1.0)? that seems like an easy test.
     
    #6 mark tomlinson, Jun 5, 2017
  7. Patrick Ryan

    Patrick Ryan Member

    Joined:
    Aug 6, 2016
    Messages:
    83
    Likes Received:
    23
    I did try swapping out the connections and it didn't change. That was why I initially changed my stepper but the problem remained. I think I'm going to change back to the old firmware and see what happens

    Sent from my SM-G930T using Tapatalk
     
    #7 Patrick Ryan, Jun 5, 2017
    mark tomlinson likes this.
  8. mark tomlinson

    mark tomlinson ༼ つ ◕_ ◕ ༽つ
    Staff Member

    Joined:
    Feb 21, 2013
    Messages:
    23,912
    Likes Received:
    7,338
    That would be my suggestion, let us know how it goes.
     
    #8 mark tomlinson, Jun 5, 2017
    Patrick Ryan likes this.
  9. Patrick Ryan

    Patrick Ryan Member

    Joined:
    Aug 6, 2016
    Messages:
    83
    Likes Received:
    23
    So, I just updated my firmware to the marlin 1.1.0 RC8 Mesh and so far the steppers seem a lot stronger. I'm doing a long test print so we will see how it goes. Correct me if I'm wrong but I believe a difference between the two is the latest marlin uses microstepping, or finer microstepping than the RC8 version. At least it seems that way when using the lcd to move things. I came across this and was wondering if maybe the increase in microstepping is decreasing the amount of current getting to the motor. https://www.pololu.com/product/2128


    “The A4988 supports such active current limiting, and the trimmer potentiometer on the board can be used to set the current limit. One way to set the current limit is to put the driver into full-step mode and measure the current running through a single motor coil while adjusting the current limit potentiometer. This should be done with the motor holding a fixed position (i.e. without clocking the STEP input). Note that the current you are measuring is only 70% of the actual current limit setting, since both coils are always on and limited to this value in full-step mode, so if you later enable microstepping modes, the current through the coils will be able to exceed this measured full-step current by 40% (1/0.7) on certain steps; please take this into account when using this method to set the current limit. Also, note that you will need to perform this adjustment again if you ever change the logic voltage, Vdd, since the reference voltage that sets the current limit is a function of Vdd”

    Either way I will let you know if it comes out ok. If it does then it'll be the first successful print in a month or so. fingers crossed.
     
    #9 Patrick Ryan, Jun 5, 2017
  10. mark tomlinson

    mark tomlinson ༼ つ ◕_ ◕ ༽つ
    Staff Member

    Joined:
    Feb 21, 2013
    Messages:
    23,912
    Likes Received:
    7,338
    Without re-tuning them ... perhaps.
    Although I would be surprised if that alone was the source of what you are seeing. (not fall down in a swoon 'surprised' but still a bit surprised).

    I have run some A4988 boards at 1/16th without any real issues.
     
    #10 mark tomlinson, Jun 5, 2017
    Patrick Ryan likes this.
  11. Patrick Ryan

    Patrick Ryan Member

    Joined:
    Aug 6, 2016
    Messages:
    83
    Likes Received:
    23
    Well the firmware wasn't the issue. Out of curiosity are the factory steppers 1 amp or 2 amp?

    Sent from my SM-G930T using Tapatalk
     
    #11 Patrick Ryan, Jun 5, 2017
  12. mark tomlinson

    mark tomlinson ༼ つ ◕_ ◕ ༽つ
    Staff Member

    Joined:
    Feb 21, 2013
    Messages:
    23,912
    Likes Received:
    7,338
    A4988 standard ones. 2 amp max... generally tuned at about 1.5a

    Sent from my SAMSUNG-SM-G930A using Tapatalk
     
    #12 mark tomlinson, Jun 5, 2017
  13. mark tomlinson

    mark tomlinson ༼ つ ◕_ ◕ ༽つ
    Staff Member

    Joined:
    Feb 21, 2013
    Messages:
    23,912
    Likes Received:
    7,338
    2 amp is max (with heatsinks) for the a4988. 1 amp w/o sinks. They will self limit.

    Sent from my SAMSUNG-SM-G930A using Tapatalk
     
    #13 mark tomlinson, Jun 5, 2017
  14. Patrick Ryan

    Patrick Ryan Member

    Joined:
    Aug 6, 2016
    Messages:
    83
    Likes Received:
    23
    Ok. I might have under tuned thinking they were 1 amp. I'll try tuning to 1.5 amp and try again

    Sent from my SM-G930T using Tapatalk
     
    #14 Patrick Ryan, Jun 5, 2017
  15. Patrick Ryan

    Patrick Ryan Member

    Joined:
    Aug 6, 2016
    Messages:
    83
    Likes Received:
    23
    What are your thoughts on the dvr8825 drivers?

    Sent from my SM-G930T using Tapatalk
     
    #15 Patrick Ryan, Jun 5, 2017
  16. mark tomlinson

    mark tomlinson ༼ つ ◕_ ◕ ༽つ
    Staff Member

    Joined:
    Feb 21, 2013
    Messages:
    23,912
    Likes Received:
    7,338
    If you run them too high the only downside is that the steppers will run hot

    Sent from my SAMSUNG-SM-G930A using Tapatalk
     
    #16 mark tomlinson, Jun 5, 2017
  17. mark tomlinson

    mark tomlinson ༼ つ ◕_ ◕ ༽つ
    Staff Member

    Joined:
    Feb 21, 2013
    Messages:
    23,912
    Likes Received:
    7,338
    On our delta I cranked them up and added heat sinks to the steppers ☺

    Sent from my SAMSUNG-SM-G930A using Tapatalk
     
    #17 mark tomlinson, Jun 5, 2017
    Patrick Ryan likes this.
  18. Patrick Ryan

    Patrick Ryan Member

    Joined:
    Aug 6, 2016
    Messages:
    83
    Likes Received:
    23
    Ok. Ill try boosting up to 1.5 amp for now and see how that does

    Sent from my SM-G930T using Tapatalk
     
    #18 Patrick Ryan, Jun 5, 2017
  19. Patrick Ryan

    Patrick Ryan Member

    Joined:
    Aug 6, 2016
    Messages:
    83
    Likes Received:
    23
    One last thing. Is the tuning amperage measured based on 3.3v or 5v? I thought I measured 5v at the vdd terminal but the thread on tuning them said something about 3.3v.

    Sent from my SM-G930T using Tapatalk
     
    #19 Patrick Ryan, Jun 5, 2017
  20. mark tomlinson

    mark tomlinson ༼ つ ◕_ ◕ ༽つ
    Staff Member

    Joined:
    Feb 21, 2013
    Messages:
    23,912
    Likes Received:
    7,338
    5v. Well 3-5v

    Sent from my SAMSUNG-SM-G930A using Tapatalk
     
    #20 mark tomlinson, Jun 5, 2017
Page 1 of 2

Share This Page