"living hinges"

Discussion in 'Design and Modeling' started by SoftBoiled, Aug 8, 2008.

  1. SoftBoiled
    SoftBoiled New Member
    hey there,

    in the material section there's a mention of "living hinges". if i'm not mistaken it's hidden joints, much like in patrick jouin's one shot stool. i wonder if there's a tutorial or a refernece somewhere on this; i couldn't find anything. if i insert a hinged part in another (separate) object - how close can both parts be together and still be functional? the same question goes for gears, springs...

    http://www.iaacblog.com/digitalfabrication/wp-content/upload s/2007/12/one-shot-stool.jpg

    thanks for the help! :)

    Last edited: Aug 8, 2008
  2. Whystler
    Whystler New Member
    A living hinge is actually a flap of plastic that bends. The flap is actually a part of part elements that are hinged together. You see this kind of hinge on a lot of flexible plastic boxes.

    Here's a good example. You know those little pots of paint? They're very smal circular vessels that hold paint, often for paint-by-number sets. The lids of these vessels are connected to the main part of the paint pot via a living hinge.


    Here's a good article about the living hinge:

    http://www.efunda.com/DesignStandards/plastic_design/hinge.c fm


    Is the Strong/White/Flexible material honestly flexible enough to make a living hinge? I can't quite anticipate that kind of flexibility based on the models I have printed in that material.

    Has anything actually been made with a living hinge here that worked that anyone can give an example of?


  3. Dalhimar
    Dalhimar New Member
    I can at least say that the WS&F material needs to be less than 1mm to become anywhere near flexible enough to do somthing such as this. I have some peices that were printed for testing and they have from .1mm to about 2-3mm parts. While the parts under .25mm were generally flexible, they would on occasion break where connected to other peices.
    I am still performing test with the material but for now i say if you want it to be flexible without being brittle, you need to have it less than .2mm in thickness while allowing it to be wider(havnt been able to check this much, will get back to you)

    The example for under .25mm was a geosphere you can see in my objects, made of a mesh that measures very small, i will get some accurate measurements soon.
  4. pete
    pete Shapeways Employee CEO & Co-Founder
    guys, WS&F is definitely fit for live hinges! I have several examples of them! I will make some pictures and put them up next week.
    As far as thickness etc, we will make a nice tutorial about the topic pretty soon, how about that?

  5. Whystler
    Whystler New Member
    Oh great Pete! I'd love to see this.

  6. bvicarious
    bvicarious New Member
    Until Pete can get his examples up I have some videos of me playing with a SWF part and putting it through some trials:


    if those don't play for you, check them out on youtube:


    So I've concluded that this material is strong, it is flexible, and it is definitely white. When I got it I thought it would snap easily, but that is certainly not the case.

    It creases a little bit, but not permanently from what I've seen. The edges on that are probably the bare minimum of 0.5mm and the middle part is probably 1mm. Some of the raised parts are 2-3 mm.

    I thought one of the interesting things was how much it snapped back after bending. Shapeways should definitely have a catapult building contest with this material ;)

  7. Whystler
    Whystler New Member
    I should respond to this by saying, thank you so much!

    These videos really demonstrate what the material is capable of in terms of flexibility. It opens up a lot of possibilities. You've done us a great service by making them :)

  8. bvicarious
    bvicarious New Member
    Thanks, I flexed it back and forth over a hundred times and it held up to the abuse. What ever creases it makes you can bend back into shape.
  9. daddymack
    daddymack New Member
    aah the humble cutting mat:) Seriously tho, thanks bvicarious, this is seriously helpful
  10. pete
    pete Shapeways Employee CEO & Co-Founder

    this took reaally long, but here are the first pictures.
    They are based on a demo model from EOS, hope it is useful.

    More about this can be found in Bart's blog today:


    Attached Files:

    Last edited: Nov 19, 2008
  11. pzich
    pzich New Member
    Thank you for doing all of this Pete.