big gears: what material to prevent buckling?

Discussion in 'Technologies and Hardware' started by rouwkema, Sep 12, 2012.

  1. rouwkema
    rouwkema New Member
    I ordered a test-print of a gear system in white strong and flexible. The size is about 15cm diameter.

    View attachment 20388

    It arrived yesterday, but I noticed that especially the large gear had buckled quite a bit. I wonder if this is due to the flexible nature of the material or whether this will be inherent to the design. Will alumide for instance give a better, non-deforming result?

    EDIT: forgot to mention, the thisckness of a single gear is 2mm
     
    Last edited: Sep 12, 2012
  2. rouwkema
    rouwkema New Member
    To make it a bit more general maybe: I think it porbably depends mainly on the thickness vs the width of these structures and the same will probably happen with bigger sheets. Anyone has any experience with what route I should follow for best results? Make the gears thicker, or choose for instance alumide (higher stiffness)?
     
  3. crsdfr
    crsdfr New Member
    It depends on what you mean by buckling. If you mean warping (ie, the part is not flat), then this is a production issue, probably caused by an operator breaking parts out while the build is still hot. There is no reason an SLS part of that size should warp under normal conditions.

    You could alleviate the issue yourself by placing the part in an oven at ~130C with a weight on top to hold it flat. Once the part is hot, remove and leave to cool naturally with the weight still on top. If it warps again instantly, try instead of leaving to cool naturally, dunking the part in cold water immediately, obviously with pressure applied to keep the part flat..
     
  4. rouwkema
    rouwkema New Member
    Thanks for the reply. Warping would indeed be a better description, but being a non-native english speaker things can be mixed up every now and then :rolleyes:

    I will give the oven treatment a try to see if that gives me flat gears.