Dice using euro coins

Discussion in 'My Work In Progress' started by Magic, Apr 16, 2012.

  1. Magic
    Magic Well-Known Member
    Hi all,

    I was considering how to combine my Truncated Sphere Dice with the new flexible squishy material, and I had the idea to make a big die where you could insert a 1 euro coin on each face (not my first design using euro coins).
    I begin with 12 faces because this was the number of countries using euro in 2001.
    The goal is to have on coin from each country and thus to select a country by throwing the die (perhaps to choose a travel destination :) ).

    Here is what it could look like:
    /openfilens/541356/photos/photo82467.jpg
    Another version would be based on a simple dodecahedron:
    /openfilens/541355/photos/photo82470.jpg
    The external holes have a radius 1 mm smaller than the coin (that is a diameter 2 mm smaller) : I hope this will allow to insert the coin but still provide a good grip.
    The internal hole are instead 2 mm smaller in radius (4 mm in diameter): the coin is not supposed to go through those ones.

    Perhaps I should add some cuts (for instance five) around the external hole to make it easier to insert the coin...

    What do you think? Will it be functional? Is it something you would like to have?

     
    Last edited: Apr 16, 2012
  2. I like it, particularly the first one. But it seems more appropriate to a rigid material, where you could simply epoxy the coins in.
     
    Last edited: Apr 16, 2012
  3. In my opinion, that won't work.
    Try to throw a round manhole cover in the manhole...
    Even with the squishy material. At least the last coin will be very problematic, because the other coins make the whole thing very rigid.
     
  4. CharGyse
    CharGyse Member
    I think they'd be able to squeeze in fine without the cuts, since the video of the material showed that it can stretch a little bit if it has to without breaking. When I was thinking about the new material, I was imagining a "canvas" built up of lots of circles like the ones on each of your faces, except I was thinking of inserting various bottle caps.

    The only problem I can see with it is coins falling out on impact when it lands - but then again I don't actually know how big or heavy a Euro coin is...
     
  5. Magic
    Magic Well-Known Member
    Thank you all for your answers.
    The reason why I prefer not the glue the coins is that I am a coin collector, so I like the idea to be able to get them back at some point.
    It is difficult to know if the coins can be inserted (and removeved) without falling, as long as the model is not prototyped. That's the beauty of 3D printing to be able to do so for (hopefully) a reasonable cost.
    There are a lot of parameters that can be tweaked to make it work like the diameter of the external hole, the number of cuts, the shape of the section (squared, rounded) the thickness and so on.

    I am afraid I will have to be patient and then give it a try...
     
  6. henryseg
    henryseg Well-Known Member
    Couldn't you make the hole exactly the right size for the coin, but with a small lip around the edge to hold it in. So the coin is recessed slightly into the die. Something like:

    Code:
    ----.       .----       
      .-'       '-.
      |           |
      '-----------'
    
     
  7. CharGyse
    CharGyse Member
    I think that's what Magic has done, the lip being 1mm in all around, but with another "lip" on the inside of the face being 2mm (presumably to let out material?).
     
  8. stop4stuff
    stop4stuff Well-Known Member
    The die looks very cool indeed.

    I don't think you'll have any problems inserting the coins, the last one might be tricky an require the use of a tool to lever the coin in, similar to the way a tyre iron is used get a car or bike tyre over the wheel rim. I don't even think you'd need cuts.
     
  9. Magic
    Magic Well-Known Member
    Thanks again for your feedbacks.
    Here is a sliced version of the model to better understand the principle:
    [​IMG]
    So yes, it is basically how you suggested, Henry and CharGyse.
    Stop4Stuff, I like the tyre analogy. I hope it will work this way.

     
    Last edited: Apr 21, 2012
  10. Magic
    Magic Well-Known Member
    I did a version for quarters as I know you can find quarters from different states or even commemorative quarters.
    I only changed some dimensions of the dodecahedron to match the size of this coin.
    Please welcome the DodQuarter:
    [​IMG]
    This is the version printed by Shapeways.
     
    Last edited: May 18, 2012