This is fun !!! This is a suggestion I made years ago, on this list, and was roundly "poo-pooed" ( as usual ) if I remember correctly. So, then, who's refined this technique and put it into practice, and where can I read about their discoveries ??? And should I use sugar pine, spruce, maple or what for the added lamination ? And what kind of glue ? ( I was thinking epoxy would have minimal creep, but then, if the rib and addition were dowelled together ( maybe with bamboo skewers ) the couldn't "skid" over each other, at all. Thump P.S. This 57" Ivers and Pond upright has very wide ribs, with nearly flat tops and a lot of room behind the posts, so it's tempting ! --- Richard Brekne <ricb at pianostemmer.no> wrote: > > Rib extenders are simply additions to the height of > the existing ribs. > They can be made with some degree of machined crown > so that when glued > they exert an upwards force on the existing > assembly. One can also put > them in a high humidity hotbox and glue them on in a > state of very high > MC so as to attempt to take advantage of their > shrinkage as they loose > MC... kind of the reverse of gluing a dried panel on > the board. That > last came to me from Ron Overs recently. I suppose > you could press the > assembly upwards as well and glue on extenders match > the surface of the > existing ribs... also a way of increasing crown. > > The point with extenders as I understand it is that > they increase > existing rib height... which does a lot more for > stiffness without > adding as much mass as adding extra ribs will. Of > course you have to > have room to place them... and if you are dealing > with very high ribs to > begin with then perhaps this is not such a good > idea. But for shallow > and wide ribs that have lost their gumption.... > seems like a good idea. > > Cheers > RicB > > "Rib Extenders "??? What's that ??? This one > has wide, flat topped > ribs,. so I thought I might laminate something ( > suggestions as per > materials appreciated ) to their tops, if I'm > not happy with the > crown I get. I'll tell you all about this > recrowning method when > I'm done, and have more to report per results. > > Peace, > Thump > > > ____________________________________________________________________________________ Looking for last minute shopping deals? Find them fast with Yahoo! Search. http://tools.search.yahoo.com/newsearch/category.php?category=shopping
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