By George Hart for the Museum of Mathematics


A string hyperboloid can be made by running strings between two circles and rotating one relative to the other. Here’s one large enough to stand inside of—it is fourteen feet high—between four-foot diameter circles.

It is easy to make your own. Just cut out two circles from a sheet of plywood, drill a series of equally spaced holes, and be prepared to tie lots of knots.

See all of George Hart’s Math Monday columns

Gareth Branwyn

Gareth Branwyn

Gareth Branwyn is a freelance writer and the former Editorial Director of Maker Media. He is the author or editor of over a dozen books on technology, DIY, and geek culture. He is currently a contributor to Boing Boing, Wink Books, and Wink Fun. And he has a new best-of writing collection and “lazy person’s memoir,” called Borg Like Me.

  • Daphne Gledhill

    Neat project. I’m thinking of making one comprised of several different colors of string.

    Daphne Gledhill
    Free Email Marketing

  • Anonymous

    It reminds me of the movie “Cube”.

  • M@

    I want to make this into a harp.