"Edwin Pawlowski" wrote in message
news:F1D_d.8889$Ue6.99@trndny04...
...
I forget where it is, but if you do a Google search for SAGULATOR you will
find a little program that will allow you to predict how much a shelf will
sag under weight.



http://www.woodbin.com/calcs/sagulator.htm

If you put 5000 lbs on a 30" x 12" x .5" l.d. MDF shelf, it deflects 70.33".
I never knew the stuff was so stretchy. :-P

BTW, I didn't see poplar listed.
--

Jerry