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

Solved Metric or Imperial smooth rods

Discussion in 'General Questions' started by DGGT6, Oct 19, 2019.

  1. DGGT6

    DGGT6 New Member

    Joined:
    Apr 11, 2019
    Messages:
    23
    Likes Received:
    7
    Hi Gents,
    just been playing around trying to get some good LM8UU bearings and have just measured the smooth X rods and they seem to be under 8.0mm, perhaps 7.93mm. This would equate with 5/16".
    Were the Robos built with 5/16" smooth rods as well as 5/16 threaded rods?

    Thanks guys,
    Doug
     
  2. Geof

    Geof Volunteer Moderator
    Staff Member

    Joined:
    Nov 9, 2015
    Messages:
    6,757
    Likes Received:
    2,339
    They are suppose to be 8mm but are cheap parts
    If you replace do 8mm and the lm8uu are a good fit :)
     
  3. mark tomlinson

    mark tomlinson ༼ つ ◕_ ◕ ༽つ
    Staff Member

    Joined:
    Feb 21, 2013
    Messages:
    23,912
    Likes Received:
    7,338
    Yea, none of the parts have been imperial since the beta (which did have 5/16 rods) Even the official R1 was metric.
     
  4. DGGT6

    DGGT6 New Member

    Joined:
    Apr 11, 2019
    Messages:
    23
    Likes Received:
    7
    Ah Ha!
    Mine had 5/16 threaded rods. Therefore a Beta version and therefore 5/16 smooth rods.
    That will explain why the LM8 bearing feel so sloppy!
    Ok, so off to buy some smooooth rods.
    What is better with LM8 bearings chromed rods or stainless rods or is there another option?

    Thanks for sorting this out guys,
    Regards, Doug
     
    Geof likes this.
  5. albert3d

    albert3d Member

    Joined:
    Feb 3, 2018
    Messages:
    70
    Likes Received:
    28
    Partbuilt3d has the chromed hardened rods that are a slight improvement over stock or stainless. They are also cheaper than their stainless. He has them custom made, so I would think the quality would be pretty good. You may find them cheaper elsewhere, but these guys are pretty great to work with and I like to support small business.

    https://www.partsbuilt.com/linear-rod-x-chrome-r1-robo/
    https://www.partsbuilt.com/linear-rod-y-chrome-r1-robo/
    https://www.partsbuilt.com/linear-rod-z-chrome-r1-robo/

    So Doug, if you have a kickstarter, does that mean your bed rails are like the drawer slides and not smoothrods?
     
    Geof, WheresWaldo and mark tomlinson like this.
  6. DGGT6

    DGGT6 New Member

    Joined:
    Apr 11, 2019
    Messages:
    23
    Likes Received:
    7
    Thanks Albert,
    curious about my Robo so far away from home down here in Australia!
    It had 5/16 threaded rods but Y axis are round rods as well. My wiring doesn't look standard so I believe there has been a lot of modding done. With alot of help from the guys on this forum I have been ironing out the bugs and learning how to get the best out of the machine and I am quite happy, (often frustrated) with my $300 Robo.
    I have had "trouble" getting LM8 bearings to fit snuggly on my Z axis but I now believe the X and Z rods were imperial 7.92ishmm whereas the Y rods are more 7.98ishmm.

    Thanks for your help,
    Cheers. Doug.
     
  7. mark tomlinson

    mark tomlinson ༼ つ ◕_ ◕ ༽つ
    Staff Member

    Joined:
    Feb 21, 2013
    Messages:
    23,912
    Likes Received:
    7,338
    For most of the R1 series, there was very little "standard" in terms of assembly.
    Worst case you could buy some bar stock and replace them all to be consistent :)
     
    Geof likes this.
  8. WheresWaldo

    WheresWaldo Volunteer ( ͠° ͟ʖ ͡°)
    Staff Member

    Joined:
    Feb 18, 2015
    Messages:
    5,905
    Likes Received:
    3,593
    Hmm, I highly doubt Robo speced two different size linear rails on the R1, my guess is a combination of Cheap Chinese rails and unfortunate assembly.
     
    mark tomlinson and Geof like this.
  9. mark tomlinson

    mark tomlinson ༼ つ ◕_ ◕ ༽つ
    Staff Member

    Joined:
    Feb 21, 2013
    Messages:
    23,912
    Likes Received:
    7,338
    Yep, I blame cheap/careless assembly for all of it.
    They were not directly built by Robo.
     
    Geof likes this.

Share This Page