John, Here's a former engineer's thoughts on flex: It doesn't matter how stiff the shaft is, if the connection to the head is flexible. The further up the shaft you go, the less important stiffness is. Both Fujan and Faulk seem to have very beefy heads, and don't rely on the traditional pipe thread connection. I'm thinking that if you stuck either of their heads on the end of a Schaff octagonal extension lever, you'd be surprised how stiff it would feel. Mike John Formsma wrote: > I'd posted this a few days ago, but maybe it got buried in Inboxes. > I'm particularly interested in those who've used the Fujan CF lever, > and their comparisons to the new Faulk lever. Also, > engineers-turned-piano techs who contribute to the list -- any input > on my questions below about deflection/flex? > > -- > JF > > ************* > Posted 3/22/09 > David [Andersen], you've used the Fujan, right? How does the new > Faulk compare? > > I'm not seeing how it could be stiffer than a hollow CF tube the > diameter of a Fujan (or Gluzman). Rigidity comes from the large > diameter of the hollow cylinder -- not from the fact that it's merely > a CF rod. The smaller the CF rod or tube, the more flex it will have. > > In other words, even if you do put a 1/2" CF rod in a 5/8" hollow > aluminum tube -- it still isn't as stiff as a Fujan. Unless there is > some (unknown-to-me) coupling effect from the two used together. And > unless it's made quite a bit shorter. If it's shorter, there won't be > as much noticeable flex. But then, you'd get that same effect in > greater proportion with the larger diameter CF tube if you used a > shorter piece there. > > I'm haven't seen a new Faulk lever yet. Nor do I know the actual > dimensions of the materials used. (I'm not an engineer, but I've > played around with some numbers some time ago.) I know it's all about > how it feels; numbers don't tell everything, but they do help. > > I await enlightenment. <G> > > -- > JF
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