<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> <HTML><HEAD> <META http-equiv=Content-Type content="text/html; charset=US-ASCII"> <META content="MSHTML 6.00.2900.2802" name=GENERATOR></HEAD> <BODY id=role_body style="FONT-SIZE: 10pt; COLOR: #000000; FONT-FAMILY: = Arial" bottomMargin=7 leftMargin=7 topMargin=7 rightMargin=7><FONT id=rol= e_document face=Arial color=#000000 size=2> <DIV> <DIV>    <FONT size=3>Ron, Terry</FONT></DIV> <DIV><FONT size=3>    OK ....The laminated rib  compared to a solid rib .  Here's another point of view.</FONT></DIV> <DIV><FONT size=3>  Ok Now I,m confused.  If were only trying to= support only 400 to 600 lbs. of down bearing force as Del inferred recently or whatever one calculates this to be, = then what's all the fuss about.  It's not that much of a load.&nbs= p; I've never seen ribs sheer, break or explode under bearing.  I've seen compression crowned boards with fat crown & bearing after 40 ,= 50 , 60 years or more that sounded wonderful & the ribs still intact & = of course others that didn't.</FONT></DIV> <DIV><FONT size=3>.  The ribs do other things in these boards like straighten out when the crown deflates but a stiff spruce crowned rib with nice tight straight grain & a laminated rib in my = mind will do just about the same thing for as long as we want them to if designed= to handle the appropriate loads. And they will do it for a tremendously long ti= me reliably. I like the whole laminated rib thing & all & there pretty = in a techno sense too but</FONT></DIV> <DIV><FONT size=3>   I'm just throwing out the question is it overkill?</FONT></DIV> <DIV><FONT size=3>  Flame suit on & feelin onry today</FONT></DIV= > <DIV><FONT size=3>   Dale</FONT></DIV> <BLOCKQUOTE style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: blue 2px solid"><= FONT style="BACKGROUND-COLOR: transparent" face=Arial color=#000000 size= =2>> Similarly, the various sectors of wood in a solid beam are not acting to <BR>> support a given load.<BR><BR>I'm not sure I understand that.<BR><BR>> Some will be trying to move with the load while other sectors will be <BR>> supporting it.<BR><BR>Yes, agreed. Some vectors m= ay be supporting the load more than a neutral <BR>piece, while others will of= fer less than neutral support. So wouldn't that <BR>mean a net stress vector o= f zero? Just like with the laminated beam, if the <BR>solid beam is not bend= ing on it's own (unloaded), the net strain is zero, <BR>and hence the net stre= ss is zero. If a load is applied, seems to me the two <BR>types of equally dimensioned beams would have a similar ability to support, <BR>i.e. simila= r MOE.<BR><BR>> If a similarly dimensioned laminated beam was used to res= ist a load a much <BR>> higher proportion of the beam will be working to support the load. Hence <BR>> the higher MOE in the laminated beam. Hop= e that makes sense.<BR><BR>No, it doesn't. But that may just be me. Seems to= me that if beams of the <BR>two types with no load will have a net strain of = zero and thus should be <BR>able to support similar loads. I understand your po= int of the greater <BR>internal stresses in the solid beam, but if they cancel= out (which them must <BR>if the solid beam is straight), there is no net stres= s and it will behave <BR>similar to the laminated beam. I suspect the solid = beam might reach failure <BR>at a lighter load than the laminated beam, but I d= on't see why the strain in <BR>relation to stress would differ.<BR><BR>Care to = try prying through my thick skull again? Or maybe I just need to <BR>take a fe= w beams and apply some loads. I'll try to do that this weekend.<BR><BR>Terry= Farrell</FONT></BLOCKQUOTE></DIV> <DIV></DIV> <DIV> </DIV></FONT></BODY></HTML>