[sdiy] Rolamite! (Seriously off topic.)

[Don Tillman]

   From: "Happy Hairy Harry" <paia2720 at hotmail.com>
   Date: Wed, 04 Apr 2001 14:42:35 -0000

   it is so simple, quiet and effective. Sort of like a Rollamite

   (anyone remember that invention that went nowhere...?)

Oh yeah!

A quick web search reveals... 

(Isn't it wonderful how somebody can bring up some totally obscure
topic and you can do a quick web search and learn something?)

First off, I see that it's spelled Rolamite.  For those who don't know
about it, this is a simple and interesting mechanical bearing.  Here's
a picture:
  http://www.bartleby.com/61/imagepages/A4rolami.html

Edmund Scientific used to carry demo Rolamites.

The original claim was that it was the seventh of the "Simple
Machines".  (The other six being screw, lever, inclined plane, pulley,
Salad Shooter, and Cuisenart.  Or something like that.)

And it's apparently used in many car air bag crash detectors:
  http://members.aol.com/carleyware/library/airbag01.htm

Very cool!

And I see that "rolamite.com" is still available.

  -- Don

-- 
Don Tillman
Palo Alto, California, USA
don at till.com
http://www.till.com