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The Infinite Hyperboloid Marble Track, Spinning Pen Holder

3D model description

### #The Infinite Hyperboloid Marble Track, Spinning Pen Holder

*The marbles on the hyperboloid go round and round, all through the tracks! *

This design is a synthesis of three previous projects, involving the hyperboloid, marble rings, and linkage bars. It is of multiple uses -- a bottomless hyperboloid holder, a revolving holder with a bottom, or an infinite marble track.

Seeing kids try to put marbles into the hyperboloid pencil holder in a previous project, I decided to add two donut structures at both ends to create an infinite hyperboloid marble track. To connect the terminal parts to the body, I referred to the snap-in design used earlier.

Marbles of a diameter between 10mm and 16mm can be used. You may need a LOT of marbles to fill the tracks. Of course, there is no need to fill the tracks. Try experimenting with ¼ or 1/3 (about 30 to 50) and see how it works.

### #Alternatively ,
If we use only one cap, we get a revolving pencil or pen holders, holding pens of a diameter between 10 mm and 16 mm.

### #Warning
Once the end parts are snapped in, it is really HARD to remove, which may be a good thing! A looser version is provided in case it is desired. Have fun and do be SAFE!

### #See Also
1. Hyperboloid Pencil Holder/Cable Organizer:

  1. Marble Rings: &

  2. Snappy Linkage Bars:

  • 3D model format: STL



STEAM educator, learning from and working with K-12 STEAM teachers to explore new ideas of teaching and engagement. I firmly believe ART is at the core of STEM learning or all human learning! I owe my ideas and designs to the hundreds of K-12 children and teachers and university professors I have had the pleasure of working with, in multiple disciplines-- math, science,engineering language arts, social studies, early childhood education and more! All mistakes, of course, are mine! There is no warranty or liability whatsoever implied or explicit behind the designs or ideas. They are all posted for their potential educational values.

When working with children, please strictly observe all safety and health procedures! Please refer to the NSTA safety guides:




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