<!doctype html public "-//w3c//dtd html 4.0 transitional//en"> <html> <body bgcolor="#FFFFFF">   Cy Shuster wrote: <blockquote TYPE=CITE> <blockquote dir=ltr style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px">Hmmmm....  Not sure where you are at here... if you mean nesting like my third drawing... then I would suppose their affects become additive. >>Yes, I mean like the third drawing.  Yes, the forces would add, but like vectors: the weak spring resists bending by "x" amount; the strong spring bends by "10x"; so the result is a bend equal to "9x".  </blockquote> </blockquote> Cy If the effect of two springs are additive, then their total resistance gets larger, not smaller. Vectors also add depending on the direction. Your vectors above are opposing vectors, and thats not whats going on when you press down on two layred leaf springs. RicB -- Richard Brekne RPT, N.P.T.F. UiB, Bergen, Norway <A HREF="mailto:rbrekne@broadpark.no">mailto:rbrekne@broadpark.no</A> <A HREF="http://home.broadpark.no/~rbrekne/ricmain.html">http://home.broadpark.no/~rbrekne/ricmain.html</A> <A HREF="http://www.hf.uib.no/grieg/personer/cv_RB.html">http://www.hf.uib.no/grieg/personer/cv_RB.html</A>   </body> </html>