Briar Rabbit writes: I'm guessin' that the intent of this rib design is to maximize support, while retaining excellent elasticity, and that the grain orientation has a lot to do with it. When you pound these boards with your fist, they make an exceedingly gratifing "THUMmmmmmmmmmm" Thump Hey there Thumpy... been thinking on your post here wondering if there was some misunderstanding as to what you meant by this. Seems like you are talking about stresses in two different directions at the same time. I wanted to take a gander at my copy of Understanding Wood today... but didnt have time and forgot to bring it home with me.. sos I couldnt check out a couple questions I had. I would guess that stretching two beams across a span one each in the two grain orientations you cite, that one would give more then the other... and I would guess this would be the <<pancaked>> (as you put it) orientation. But at the same time lengthwise I suppose their properties would be rather identical... seems self evident really. I did get a chance for a realllllly basic (as in elementary) deflection test today... real uncontrolled and quite suspect to be fair... but just so.. .What I did was simply put lateral pressure on the ends of a small stick to see which way it bent when it first gave.... and sure enough... (also seems rather self evident) it always bent with the <<pancake>> direction. Now... I didnt get a chance to read what da book has to say on relevant controlled stress tests to so I'm not going to state anything authoritively... and it WOULD be a good idea to do some real digg'n to find out the straight skinny to be sure.... but if you are saying (amoung other things) that ribs with grain orientation horisontal vs vertical would have different overall support characteristics... then I suppose the (mine anyways) unschooled intuitive conclusion would tend to agree.. That said... I'll be the first to bow to any real proof to the contrary.... which should be easy enough to find one way or the other me thinks. Cheers RicB
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