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

better hobbed bolt

Discussion in 'Mods and Upgrades' started by CAMBO3D, Jul 6, 2013.

  1. Peter

    Peter Member

    Joined:
    Jun 20, 2013
    Messages:
    81
    Likes Received:
    40
    Happy 4th, United States of America!

    Ok, so my hobbed bolts arrived today. Yay!
    It Fits, it fits very well. Not sure yet on the actual improvement in a long duration print though, so I'll have to print a few things, but with only a few washers as expected, the hob sits very nicely over the hole and now I'm steering the horse by it's head, not its 'nuts'.
    I think 26mm would be just too short, and 29mm does reduce the engagement of the gears a little, I'd guess 27.5-28 would be ideal for the robo3d as a stock upgrade. But, have some extra shim washers handy, the clunky 'machine' washers that came with the hobbed bolts are all about 1.3mm thick, i had some m8x0.5mm thick shim washers to help with hob placement.

    My aluminum can shim tactic on the bolt head was a little tricky but worked a treat in the gear recess.

    I'll leave the bolt long because i can tighten the nyloc nut down on the plain hex to lock the bolt effectively, it doesnt impact on thex carriage ends at all.

    Updates on this bolt over the next couple of days

    20140704_232357.jpg 20140705_004402.jpg 20140705_004433.jpg
     
    2 people like this.
  2. Peter

    Peter Member

    Joined:
    Jun 20, 2013
    Messages:
    81
    Likes Received:
    40
    Subjectively, so far it's good, I'd recommend it. 3hrs of printing and no pla dust whatsoever in the hob.
     
    4 people like this.
  3. mark tomlinson

    mark tomlinson ༼ つ ◕_ ◕ ༽つ
    Staff Member

    Joined:
    Feb 21, 2013
    Messages:
    21,373
    Likes Received:
    7,045
    And there you go :)
     
  4. tesseract

    tesseract Moderator
    Staff Member

    Joined:
    Feb 20, 2013
    Messages:
    1,924
    Likes Received:
    533
    Also remember you can as I did reverse the direction of the bolt itself to give you even more versatility.
     
  5. Peter

    Peter Member

    Joined:
    Jun 20, 2013
    Messages:
    81
    Likes Received:
    40
    This hobbed bolt is uni-directional in terms of its drive design, I can post one to someone in Australia (at cost) if you want to try it. I bought the 3 pk, so I can afford to pass one on.

    I think this bolt will work even better on softer materials like abs, and with a little work, i even reckon it could drive ninja-flex ok.
     
  6. Darkhunter12

    Darkhunter12 New Member

    Joined:
    Apr 5, 2014
    Messages:
    109
    Likes Received:
    8
    Peter, I live in Australia and am interested, I am sick and tired of good long prints stuffing up due to a simple and cheap thing like this! I will inbox you if you still have some :)
     
  7. John H

    John H Member

    Joined:
    Apr 19, 2014
    Messages:
    81
    Likes Received:
    9
    So has anyone used the new Bolt with flexPla or Ninjaflex, I was going to do the brass tubing mod as I read that , That will help feed the softer material.
     
  8. mark tomlinson

    mark tomlinson ༼ つ ◕_ ◕ ༽つ
    Staff Member

    Joined:
    Feb 21, 2013
    Messages:
    21,373
    Likes Received:
    7,045
  9. Peter

    Peter Member

    Joined:
    Jun 20, 2013
    Messages:
    81
    Likes Received:
    40
    My spare bolt is spoken for.
     
  10. Peter

    Peter Member

    Joined:
    Jun 20, 2013
    Messages:
    81
    Likes Received:
    40
    Update:

    I've done several "all nighter" 14hr+ prints without problems.

    The only time I've had a feed issue, was my own fault, as I had the left the hotend idling at 195 for an hour and a half between prints and restarted. The filament had heat soaked a bit and was soft enough that the hob chewed it. This is exacerabated by my starting method, where I have the nozzle almost touching the glass to begin and turn the z rods to raise the HE while printing the skirts untill I'm happy with the layer.
     
  11. Steve K.

    Steve K. Member

    Joined:
    May 10, 2014
    Messages:
    82
    Likes Received:
    14
    Also ordered just in case I need it ........................
     
  12. mark tomlinson

    mark tomlinson ༼ つ ◕_ ◕ ༽つ
    Staff Member

    Joined:
    Feb 21, 2013
    Messages:
    21,373
    Likes Received:
    7,045
    Spare parts are always handy :)
     
  13. Steve K.

    Steve K. Member

    Joined:
    May 10, 2014
    Messages:
    82
    Likes Received:
    14
    True, especially if they are only $4.00 each. I bought 4.
     
    2 people like this.
  14. Technidyne

    Technidyne Active Member

    Joined:
    Apr 18, 2014
    Messages:
    229
    Likes Received:
    229
    Just ordered a few of these bolts as well and will do this modification. Long prints are iffy as my filament sometimes kinks after the hobb as well.
    Trying to clear a kinked filament last night, one of the 4mm x 50mm bolts with the spring flew across the workshop never to be seen again, so off to the hardware store I go today:(
     
    Tom Finzel likes this.
  15. Steve K.

    Steve K. Member

    Joined:
    May 10, 2014
    Messages:
    82
    Likes Received:
    14
    I understand your problem. Sometimes I put screws and nuts on my work bench and they just disappear.
     
  16. Denys Dmytriyenko

    Denys Dmytriyenko Active Member

    Joined:
    Nov 29, 2013
    Messages:
    119
    Likes Received:
    59
    @Technidyne I don't think your kinked filament is due to the bad hobb. It probably grips it good enough to push it hard down the hotend, but some sort of clog is preventing it, hence the kinking...
     
  17. mark tomlinson

    mark tomlinson ༼ つ ◕_ ◕ ༽つ
    Staff Member

    Joined:
    Feb 21, 2013
    Messages:
    21,373
    Likes Received:
    7,045
    If this is PLA, I suggest you season the hotend.
    That is what nuked these from orbit for me. It has never happened since.
    Replacing the stock hobbed bolt cured 98% of these, that last step finished it off.
     
  18. Technidyne

    Technidyne Active Member

    Joined:
    Apr 18, 2014
    Messages:
    229
    Likes Received:
    229
    How does one "Season The Hotend"? ....lizard's tail, left eye of an owl, voodoo? LOL!:)
     
    #138 Technidyne, Aug 2, 2014
    Last edited by a moderator: Aug 2, 2014
    Tom Finzel likes this.
  19. mark tomlinson

    mark tomlinson ༼ つ ◕_ ◕ ༽つ
    Staff Member

    Joined:
    Feb 21, 2013
    Messages:
    21,373
    Likes Received:
    7,045
  20. mark tomlinson

    mark tomlinson ༼ つ ◕_ ◕ ༽つ
    Staff Member

    Joined:
    Feb 21, 2013
    Messages:
    21,373
    Likes Received:
    7,045
    Rather than re-season periodically I just installed an 'oiler' (from thingiverse, there are a few to choose from).
    I then just add a few drops of oil every couple of days (depends on print load).

    [edit: to be clear you put a sponge in the oiler and add the oil to it, then refresh it with more every so often--the PLA passes through the oiler on its way to the hotend and picks up a small amount as it is feeding in]
     
    #140 mark tomlinson, Aug 2, 2014
    Last edited by a moderator: Aug 2, 2014

Share This Page