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

Serious Bed Homing Problem

Discussion in 'Troubleshooting' started by adikted2astro, Jun 25, 2019.

  1. adikted2astro

    adikted2astro Active Member

    Joined:
    Aug 10, 2017
    Messages:
    223
    Likes Received:
    67
    Ah...............but doesn't the current IR sensor (and Filastruder version) run on 5V? Do you mean the physical size of the wires?
     
  2. adikted2astro

    adikted2astro Active Member

    Joined:
    Aug 10, 2017
    Messages:
    223
    Likes Received:
    67
    I'm glad I'm not the only one that feels this way :)
     
  3. WheresWaldo

    WheresWaldo Volunteer ( ͠° ͟ʖ ͡°)
    Staff Member

    Joined:
    Feb 18, 2015
    Messages:
    5,806
    Likes Received:
    3,521
    I am pretty sure the lines for the IR are 3.3V and the signal is referenced to gnd. Look at what you need to do on the BLTouch website,
    You need servo wiring and sensor wiring, so they have to have different pins set up, which also means a firmware update, https://www.antclabs.com/wiring

    You can use Robo's firmware if you pull it from their GITHUB and edit the configuration to enable the servo, but since the board is proprietary I don't know if they extended the lines for the servo control to a connector.
     
  4. WheresWaldo

    WheresWaldo Volunteer ( ͠° ͟ʖ ͡°)
    Staff Member

    Joined:
    Feb 18, 2015
    Messages:
    5,806
    Likes Received:
    3,521
  5. mark tomlinson

    mark tomlinson ༼ つ ◕_ ◕ ༽つ
    Staff Member

    Joined:
    Feb 21, 2013
    Messages:
    21,111
    Likes Received:
    6,997
    I think it is safe to say they did not.
     
  6. adikted2astro

    adikted2astro Active Member

    Joined:
    Aug 10, 2017
    Messages:
    223
    Likes Received:
    67
    Yeah I think it would be much easier to try the other IR sensor first. However, the BLTouch is attractive because it can basically be used with any bed. I did some research into the different types of homing sensors and the IR sensors should do well even on glass. Specifically, that Filastruder version performed well in all of the tests I've seen online. Robo just HAD to go proprietary though, didn't they?
     
  7. adikted2astro

    adikted2astro Active Member

    Joined:
    Aug 10, 2017
    Messages:
    223
    Likes Received:
    67
    I saw a test done on something like 12 different sensors, inductive, capacitive, mechanical, IR, and in every single test, all of the sensors performed better (as far as standard deviation is concerned) with a cold bed; much, much better. I have to say that in my limited experience, this is the case for the Robo IR sensor. I switched back to homing on a cold bed a couple of days ago. Before that, I was heating the bed to 60C, then heating the nozzle to 150C before homing. That's when I was having these problems. But, since going back to a cold bed/nozzle, I haven't really had any of those problems (knock on wood).

    Since this is working, I'll stick with it. The next time I perform UBL from the start, I will do so on a cold bed. My mesh is nearly perfect right now, so I don't see any benefit in redoing it. Every time I've done UBL, I used a 60C bed and 150C nozzle because it was suggested. However, if the sensor performs better on a cold bed, then there's no need to heat everything up. This might reduce the number of iterations I have to complete before printing a good mesh.
     
    WheresWaldo and mark tomlinson like this.
  8. WheresWaldo

    WheresWaldo Volunteer ( ͠° ͟ʖ ͡°)
    Staff Member

    Joined:
    Feb 18, 2015
    Messages:
    5,806
    Likes Received:
    3,521
    Good sleuthing
     
  9. tkoco

    tkoco Active Member

    Joined:
    May 7, 2018
    Messages:
    190
    Likes Received:
    96
    Sort of makes sense. IR sensor looks at a reflection of an IR transistor off of the bed to set it's thresholds. Heating the print bed before engaging the IR sensor is a recipe for disaster for several reasons:

    1) the sensing environment is altered by the addition of heat from the print bed

    2) the heating element of the print bed does not evenly heat the surface of the bed. The typical structure of the print bed uses aluminum to spread the heat out mode evenly ( similar to aluminum cookware ). Since the IR sensor routine measures individual point on the bed, it is probable that the points could be at different temperatures. Which points back to step 1).

    3) When the print bed heats up, it expands.

    In summary, do auto-leveling on a cold bed or allow the heated print bed to stabilize before engaging the auto-level. (ie. wait 5 minutes after the print bed reaches temperature)
     
  10. adikted2astro

    adikted2astro Active Member

    Joined:
    Aug 10, 2017
    Messages:
    223
    Likes Received:
    67
    Yeah it makes sense to me. I just wish I had thought it out sooner. The only reason I've been using a hot bed and nozzle is because that's what the instructions said for UBL, and G29 for that matter. But no more.......
     
  11. Joseph Stevens

    Joseph Stevens New Member

    Joined:
    Aug 25, 2017
    Messages:
    5
    Likes Received:
    0
    Sorry if this was covered above and I missed it, but when I was having problems with the IR sensor, I was told by Robo to just disable it, since apparently it didn't actually do anything useful.
     
  12. mark tomlinson

    mark tomlinson ༼ つ ◕_ ◕ ༽つ
    Staff Member

    Joined:
    Feb 21, 2013
    Messages:
    21,111
    Likes Received:
    6,997
    Wrong IR sensor :) You mean the one that detects filament, they mean the one that does the autoleveling
     
  13. Joseph Stevens

    Joseph Stevens New Member

    Joined:
    Aug 25, 2017
    Messages:
    5
    Likes Received:
    0
    No, I mean the autoleveling sensor. Here's the email I got from Robo a few months ago:

    Hi Joseph,

    Unfortunately we are out of the IR sensors so if it is not working properly, we can disable the autoleveling feature (it actually doesn't do anything for the print, or printer - it doesn't work) I have it disabled on my printer, it just homes, then starts printing. To do this:

    Please go to your octoprint server (web dashboard) and go to settings at the upper right, then Gcode Scripts, then "Begining of the print" section. There you will see the command G36. remove G36. Replace it with G28. This will disable the "autolevel"

    First set all the bed adjustment nuts to the neutral position when the nut head and the threads of the screws are flush. You should just barley be able to feel the screw sticking out from the nut head.

    Now run the Z offset wizard.

    Once finished, run the Bed Calibration wizard. Now your print bed should be very level.

    For a very steady hold, Put some silicon glue, some school glue, or some non-permanent thread locker on the threads of your adjustment nuts while you are running the bed calibration wizard. Once you have it dialed in, let the glue set.

    Make sure you have gotten rid of G36 from any start G code you use in other slice engines.

    Now do a test print. You will notice its a much quicker start procedure and very level.

    just run your prints with G28 and it should be perfect every time.
     
  14. mark tomlinson

    mark tomlinson ༼ つ ◕_ ◕ ༽つ
    Staff Member

    Joined:
    Feb 21, 2013
    Messages:
    21,111
    Likes Received:
    6,997
    Yes, you can disable autoleveling and use manual leveling ... that is certainly true.

    To say that it does nothing useful is disingenuous to say the least.
    It can do a lot to help with a warped bed (if you use MESH or Unified Bed leveling)

    You simply can't use any automatic bed leveling without it.
     
  15. albert3d

    albert3d Member

    Joined:
    Feb 3, 2018
    Messages:
    48
    Likes Received:
    18
    Looks like part partsbuilt.com is trying to source the IR sensor for the R2/C2. So get on their notification list if you want to just get a stock Robo one. I still say getting the Duet IR sensor and retrofitting it onto the fanshroud is the best way to go for $24. Below is a thingiverse link to a guy that went all in and did the Duet IR, E3DV6 and custom fan shroud. I think the stock shroud and hotend should still work just fine if you just redesign the cover for the IR to hold the Duet IR at the same height as stock and mount in the original holes.

    https://www.partsbuilt.com/bed-sensor-r2c2-robo3d/

    https://www.thingiverse.com/thing:3180056
     
    mark tomlinson likes this.

Share This Page