Skip to content

Geodesic Sphere (Printed connectors + straws)

Advertising
Advertising
?
Creation quality: 5.0/5 (1 vote)
Evaluation of members on the printability, utility, level of detail, etc.

  • 4.1k views
  • 5 likes
  • 80 downloads

License
3D design format
SCAD and STL Folder details Close
  • 12x_5way_plated.stl
  • 30x_6way_plated.stl
  • 5way.stl
  • 6way.stl
  • geodesic_connector.scad

Learn more about the formats

Publication date 2021-02-21 at 20:29
?
Published to Thingiverse on: 2019-07-16 at 19:59
Design number 306040

3D printer file info

3D model description

Want to make something a bit BIGGER than your regular 3d prints? This geodesic sphere is super easy and fun to build!

Just print 12 of the 5-way connectors and 30 of the 6-way connectors, then connect it all up using straws! No glue, screws, support, or any other materials are needed. The result is a beautiful, solid 2v geodesic sphere with 42 vertices and 80 triangles. There are 120 struts, which can be made from 60 straws for a small sphere or 120 straws for a big one.

I recommend using paper straws, like these that I bought from Amazon: http://amzn.com/B07JR64BSK

Assembly Instructions

  • Calculate your strut sizes and cut your straws.
    • If your straws are 197mm like those linked above, then I recommend:
      • Small sphere: use 60 straws, each cut once to create 93mm short strut and a 104mm long strut
      • Long sphere: use 60 full length straws as your long struts, and 60 straws cut to 152mm as your short struts
    • If your straws are a different length, just make sure your struts obey the equation (LONG - 12)/(SHORT - 12) = 927/820. This is because the connectors add 6mm to each side of each strut.
  • Print a test piece to check straw fit.
    • Ideally it takes significant force to push the straw on so that it can hold some tension (after all, geodesics are a tensegrity structure!). If it's too tight though and you cant slide the straw all the way on, raise PLUG_CLEARANCE in the SCAD file to a less negative value (and vice versa if too loose).
  • Print 12x 5-way connectors and 30x 6-way connectors. No support is needed, but add a brim if you have problems with adhesion to the bed.
  • Attach all the short straws to the 5-way connectors
  • Build the rest of the sphere using this simple rule: "short straws connect to short straws". This means each short strut on each 5-way piece will have a 6-way connector on the end, with another short strut coming off the directly opposing (in-line) side of the connector. The other 4 plugs on the 6-way connector will each get a long-strut (you can think of the long-struts as forming the sides of the pentagons surrounding the 5-way connectors)

I'm working on some very cool related Things that hopefully I'll be posting soon!

Tags

Advertising


Issue with this design? Report a problem.

Would you like to support Cults?

You like Cults and you want to help us continue the adventure independently? Please note that we are a small team of 3 people, therefore it is very simple to support us to maintain the activity and create future developments. Here are 4 solutions accessible to all:

  • ADVERTISING: Disable your banner blocker (AdBlock, …) and click on our banner ads.

  • AFFILIATION: Make your purchases online by clicking on our affiliate links here Amazon.

  • DONATE: If you want, you can make a donation via Ko-Fi 💜.

  • WORD OF MOUTH: Invite your friends to come, discover the platform and the magnificent 3D files shared by the community!


Sharing and downloading on Cults3D guarantees that designs remain in makers community hands! And not in the hands of the 3D printing or software giants who own the competing platforms and exploit the designs for their own commercial interests.

Cults3D is an independent, self-financed site that is not accountable to any investor or brand. Almost all of the site's revenues are paid back to the platform's makers. The content published on the site serves only the interests of its authors and not those of 3D printer brands who also wish to control the 3D modeling market.

100% secure payment by credit card, PayPal, Apple Pay, Google Pay, etc.
View all payment options.