ISEN-ASTC-L is a service of the Association of Science-Technology Centers
Incorporated, a worldwide network of science museums and related institutions.
*****************************************************************************

Hello Frode,

If you can't find a robust version...

Try replacing the plastic gears with metal gears.  Check out your local
machine shop or engineering supply house and send them the plastic gear to
match the tooth number, pitch, bore size etc...  

I expect your problem is visitors cranking the machine too fast.  Consider
adding an external crank knob that distances the visitor from the machine,
linked by an o-ring belt that allows some slip, and/or a small slip clutch.
Or replace the metal crank handle with a small finger knob that limits the
torque your visitors can put on the machine.

I find that almost all consumer products have a certain life expectancy in a
museum environment.  You could replace the actual music box with an
electronic version that uses light sensors, but that wouldn't be half as
fun.

Good luck,

-Eric


*****************************************
Eric Yuan
Exhibit Developer
Children's Museum of New Hampshire
6 Washington St
Dover, NH 03820
(603) 742-2002
www.childrens-museum.org
*****************************************

***********************************************************************
For information about the Association of Science-Technology Centers and the Informal Science Education Network please visit www.astc.org.

Check out the latest case studies and reviews on ExhibitFiles at www.exhibitfiles.org.

The ISEN-ASTC-L email list is powered by LISTSERVR software from L-Soft. To learn more, visit
http://www.lsoft.com/LISTSERV-powered.html.

To remove your e-mail address from the ISEN-ASTC-L list, send the
message  SIGNOFF ISEN-ASTC-L in the BODY of a message to
[log in to unmask]