Welcome to Our Community

Some features disabled for guests. Register Today.

How to accurately join C-Beam end-to-end

Discussion in 'General Talk' started by BobC, Apr 20, 2017.

  1. BobC

    BobC New
    Builder

    Joined:
    Apr 5, 2017
    Messages:
    6
    Likes Received:
    0
    How can I extend the length of a C-Beam actuator (with end mount in place) with a second length of C-Beam such that alignment is guaranteed?
    I have an application that requires a 900mm long element to be moved over 800mm. I can achieve the movement with a 1000mm C-Beam actuator, and would then need a second piece of track with another gantry plate so that my moving element (another C-Beam) can be attached to the driven and idling gantry plates.
    The two sections of track would then need to be in precise alignment to keep the two gantry plates running true.
    Effectively what I need is a long C-Beam, with the screw end mount partway down it. Is there a good way to achieve this?
     
  2. Rick 2.0

    Rick 2.0 OpenBuilds Team
    Staff Member Moderator Builder

    Joined:
    Dec 20, 2013
    Messages:
    1,438
    Likes Received:
    582
    Assuming you are using C-beam XL gantry plates or something similar riding on the outer channels of the C-beam what you're asking seems possible. You'll need to do a bit of precision milling on the intermediate C-beam end mount though, shaving down the top so the gantry carriages can cross and milling out a beveled groove in the sides to match the v-slot channel for the wheels to pass. You will also probably want to use some alignment dowels in the in the C-beam end holes, including matching holes through the intermediate end plate and a substantial backer beam across the whole assembly.

    You haven't provided any information on the mass of the moving load but assuming it is fairly substantial you may also want to tension the screw to prevent bowing. This is done by reversing the end plates and using thrust bearings in place of the regular radial bearings and slightly tensioning the screw prior to tightening the lock collar.

    It would be helpful if you could provide a configuration diagram and give a better idea of the nature of use and the loading.
     
  3. BobC

    BobC New
    Builder

    Joined:
    Apr 5, 2017
    Messages:
    6
    Likes Received:
    0
    Hi Rick - I'll try to prepare a diagram, but in the meantime just let me add that the non-driven gantry plate does not need to pass the end mount. It only travels on the extension piece, and the driven gantry only on the main section. Does that affect your opinion on how to join them?
    As for load - this enquiry is related to my previous question about z-axis loading and support, where you kindly advised me of the use of thrust bearings. This is my model railroad track elevator, with one assembly either side of a doorway. The load will comprise a further C-Beam actuator with motor plus a couple of kg extra for my moving model railroad track.
    Actually, the only reason I am going for this two-stage approach (like a full-extension drawer slide) is that I can't get a C-Beam actuator with 1400mm travel, which is what i actually need.
     
  4. Jonathon Duerig

    Builder

    Joined:
    Nov 25, 2015
    Messages:
    216
    Likes Received:
    117
    If you want a C-Beam actuator with 1400mm of travel, the simplest option is to create a belt or rack and pinion drive system using a 1500mm C-Beam rail as the linear guide. If you use a standard C-Beam gantry plate, that should give you almost exactly 1400mm of travel.

    -D
     
  5. Rick 2.0

    Rick 2.0 OpenBuilds Team
    Staff Member Moderator Builder

    Joined:
    Dec 20, 2013
    Messages:
    1,438
    Likes Received:
    582
    In that you don't have any wheels crossing the center point then it won't be necessary to cut the intermediate plate to accommodate and if your traveling beam is high enough you won't need to trim the top. As nothing is crossing the center, using the regular gantry plates with the inset wheels is also an option.

    As Jonathan noted, belts are also an option. There are also other possibilities with screws but I will need to see a diagram to offer anything more specific.
     
  6. BobC

    BobC New
    Builder

    Joined:
    Apr 5, 2017
    Messages:
    6
    Likes Received:
    0
    Hi Jonathon - I had considered belts, but as this is a vertical application I was concerned that when power is removed from the motor, the whole thing would be free to descend under its own weight. That could be expensive! That shouldn't be a problem with a screw drive, I think.
    It is a shame that there isn't a screw end mount that can be slid into the inner channels of the C-Beam and secured at any point along its length. That would remove the need for me to join tracks and would keep things aligned.
    Is there any physical reason that one could not be made?
     
  7. Rick 2.0

    Rick 2.0 OpenBuilds Team
    Staff Member Moderator Builder

    Joined:
    Dec 20, 2013
    Messages:
    1,438
    Likes Received:
    582
    What you're suggesting is fully possible and basically what I was alluding to above by "other possibilities". A small block about 40x20x20mm with an 11/32" hole for the screw and a couple of transverse 5mm holes 20mm apart to secure it into tee-nuts in the bottom channel would do the trick. You would need to create a recess for the bearing but if you don't have the machinery for this, there are other ways to get there.
     
  8. CiaraB

    CiaraB OpenBuilds Team
    Staff Member Moderator Builder

    Joined:
    Aug 23, 2016
    Messages:
    33
    Likes Received:
    17
    Hello Bob. Thank you for your question.

    Currently, the longest length C-Beam we offer is 1500mm. This ensures the highest quality and tolerances.

    That being said, customers have successfully joined V-Slot end-to-end for their Builds using Joining Plates and/or Double Tee Nuts.

    You should be able to apply this method to C-Beam as well.


    You can find some of these Joining Plates in the examples below;

    Double Tee Nut™

    2 Hole Joining Strip Plate

    3 Hole Joining Strip Plate

    We hope this helps and we look forward to seeing your Build posted in the Build Category!
     

Share This Page