Right, I know, but my point was 100 pounds on that beam should bend it much farther down than 1/10 of 1mm. I am not believing SW's numbers though it is probably something we aren't doing right. If I had 3 beams here I would find something one hundred pounds and tie a string in the middle of the beam (with both ends fixed to the other beams) and I bet a dollar to a doughnut that beam deflects way more .1mm and my jaw would drop if it didn't.
