This is a multi-part message in MIME format. ---------------------- multipart/mixed attachment > Ron, Terry > OK ....The laminated rib compared to a solid rib . Here's another > point of view. > 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. My loading of new boards these days is typically half again over 600 lbs. >It's not that > much of a load. 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. No, the ribs don't usually explode, but I have seen broken ribs in the high end two or three times. In this part of the country, it's rare to find old compression crowned boards with decent crown and bearing. > . 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 time reliably. I like the > whole laminated rib thing & all & there pretty in a techno sense too but > I'm just throwing out the question is it overkill? > Flame suit on & feelin onry today > Dale Could be. Laminating costs me time to glue them up, but saves me time to cut them out. It uses spruce with grain angles and color defects that would otherwise not be usable in belly work, so it's good conservation of materials. I like that part a lot, but then I'm still laminating bridges from salvaged maple racquetball court flooring. In fact, at the cost of a little extra time, I can build up ribs over two or three clampings, that use up the shorter cutoffs that would otherwise be trash, on the rib bottoms where the feathering would cut away and waste good wood anyway. See photo. I also found it bothersome to bend, clamp, and try to rip ribs to depth accurately with solid ribs, especially the tighter radii in the treble. With laminated, it's simple, accurate, and more easily controllable. As far as performance goes once they're in the piano, I doubt there's much difference. Ron N ---------------------- multipart/mixed attachment A non-text attachment was scrubbed... Name: rib blanks.jpg Type: image/jpeg Size: 42891 bytes Desc: not available Url : https://www.moypiano.com/ptg/pianotech.php/attachments/a0/25/99/bb/ribblanks.jpg ---------------------- multipart/mixed attachment--
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