Welcome to Our Community

Some features disabled for guests. Register Today.

HGR 20 atop cbeam

Discussion in 'CNC Mills/Routers' started by DarkPenguin, Jan 5, 2022.

  1. DarkPenguin

    DarkPenguin Well-Known
    Builder

    Joined:
    Sep 16, 2017
    Messages:
    201
    Likes Received:
    65
    So,

    I have a bunch of linear rails. I also have a bunch of cbeam. I'd like to put the HGR 20 on top (40mm side) of the cbeam. It seams like there are few options.

    I can offset it and mount it to either of the vslots. Not enthused about this as it makes other things a pain. Plus it looks silly.
    Offset.PNG
    I can create a shim. Drill it out for the vslot screws and then drill and tap it for the hgr20 screws.
    shim.PNG
    I could also just mount it to the center and drill and tap the actual cbeam. That is like 1.8mm aluminum and I'm not sure that is enough. Plus the center bit is like 10mm wide. Seems like teetering a 20mm wide piece of steel on thin aluminum is asking for trouble.
    centered.PNG
    Any thoughts on this? I have the rails. I'm not going to do the project I bought them for so I might as well use them.
     
  2. Giarc

    Giarc OpenBuilds Team
    Staff Member Moderator Builder Resident Builder

    Joined:
    Jan 24, 2015
    Messages:
    3,008
    Likes Received:
    1,676
    I went with the first option. But mine are 15s not 20s. It is the least amount of work and I found that the M4 drop in T-nuts centered the rail nearly perfectly according to my dial indicator. By nearly perfectly, I mean there is no way I would be able to get them any straighter.
    upload_2022-1-4_22-56-20.png
     
  3. DarkPenguin

    DarkPenguin Well-Known
    Builder

    Joined:
    Sep 16, 2017
    Messages:
    201
    Likes Received:
    65
    I wanted the 15s but they were all of like $3 less than the 20s and I couldn't get myself to go for them. For this purpose they'd be much better.

    I'm re-evaluating the first option. It just looks the cleanest.

    Thanks for the input!
     
  4. Rob Taylor

    Rob Taylor Master
    Builder

    Joined:
    Dec 15, 2013
    Messages:
    1,470
    Likes Received:
    748
    Linear rail is non-structural. Which part of the beam bends the least?
     
  5. DarkPenguin

    DarkPenguin Well-Known
    Builder

    Joined:
    Sep 16, 2017
    Messages:
    201
    Likes Received:
    65
    Well, if I eventually move the drive mechanism out and put 4020 in the cbeam it is probably all pretty good. But closer to the fully supported side would be best I should think.
     
  6. DarkPenguin

    DarkPenguin Well-Known
    Builder

    Joined:
    Sep 16, 2017
    Messages:
    201
    Likes Received:
    65
    I suppose I could just buy the 2x3 steel and ditch the cbeam.
     
  7. Giarc

    Giarc OpenBuilds Team
    Staff Member Moderator Builder Resident Builder

    Joined:
    Jan 24, 2015
    Messages:
    3,008
    Likes Received:
    1,676
    Yeah, but then you have to drill a bunch of really well aligned holes. I was too lazy.
     
  8. Banjopete

    Banjopete New
    Builder

    Joined:
    Nov 10, 2020
    Messages:
    29
    Likes Received:
    30
    You could also spend a few bucks and take it to a machine shop and get them to do this critical part for you. Might be a worthwhile spend if you're going that way, maybe luck out and find a hobby machinist that can help you out locally.
     

Share This Page

  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.
    Dismiss Notice