Posted by Kaegi on Monday, May 22, 2006 at 7:08PM :
In Reply to: The Ding test, just as with crystal.... posted by Bob Thompson on Monday, May 22, 2006 at 2:07AM :
on a coil spring I can see your logic but on a brake shoe return spring the coils are pressing hard against each other so no ring can sing. If the return spring is overheated and stretched, it will ring as there is no tension to absorb the vibrations.