120-Cell in the Ball Model

120-Cell in the Ball Model

I'm following Scott Vorthmann's lead and trying out Sketchfab :)

Here is the 120-cell in the ball (fisheye) model of spherical geometry. I made this to print on Shapeways, but the outer edges end up very thin and I'm getting wall thickness warnings. Even if I bump up the edge thickness, the edges remain very thin in the radial direction because of the model. Shapeways didn't outright reject, so maybe it's worth a try to print this anyway.
https://skfb.ly/PGqw

Comments

  1. Roice NelsonJune 19, 2016 at 7:51 AM

    Btw Scott Vorthmann, I'm wondering if the vertices of the 120-Cell in the ball model lie in the golden field, and might work decently in zome. I need to try it out!

    ReplyDelete
  2. Scott VorthmannJune 19, 2016 at 7:56 AM

    Roice Nelson the vertices must be in the field, if you do all operations within it. Let's talk later about the operations.

    ReplyDelete
  3. Melinda GreenJune 19, 2016 at 3:39 PM

    What a fecund mind you have, Roice! I suspect it's worth printing because of its interesting physical properties. Maybe it bounces very efficiently or is surprisingly rugged.

    ReplyDelete
  4. Roice NelsonJune 19, 2016 at 4:25 PM

    Thanks for the compliment Melinda Green. I decided to go ahead and order after reading your comment. Luckily they have 20% off this weekend too :D Here's hoping it turns out to be printable!

    ReplyDelete
  5. Melinda GreenJune 19, 2016 at 6:40 PM

    Roice Nelson
    I don't know if they still support the "print-it-anyway" option but I had used that to see what living hinges looked like at varying thicknesses less than 1mm. (Answer, anything less than 0.5mm gets clamped to 0.5mm) Please report your result.

    ReplyDelete
  6. Roice NelsonJune 20, 2016 at 12:14 PM

    Update: The model passed manual review and is off to the printers! I'll be sure to post pictures of the result when it arrives.

    I went ahead and made the model public with no markup on my shapeways shop.
    http://shpws.me/Mllz

    I printed at approximately 9cm in diameter, and I didn't optimize for cost (using hollowing for example, like Henry and I did on some of our hyperbolic models). It's pricey, at almost $90, so sneaking in with the 20% off coupon this weekend was nice.

    ReplyDelete
  7. Roice NelsonJune 25, 2016 at 1:46 PM

    Melinda Green, this showed up today, and it's great! A really nice way to study the 120-Cell. I put a couple photos here:

    https://goo.gl/photos/8bkvfQNLGtHP4p6n9

    The thin outer edges flex a little when pushed, but are plenty strong. Their curvature seems to help the rigidity.

    There was a small issue with the model however (a stray ribbon of material that isn't supposed to be there), which I've written shapeways about. I want to fix that before anyone orders, so I temporarily disabled it on the shop.

    ReplyDelete
  8. Melinda GreenJune 25, 2016 at 9:40 PM

    Roice Nelson
    Cool! So what does it feel like? Does it bounce or wiggle or show any surprising properties? It looks great. I wonder if this is the first time it's existed in this galaxy. :-)

    ReplyDelete

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