It's a graphic illustration not one derived from actual data, it's an illustration. You press the board down it gets progressively stiffer. You're not suggesting that the deflection of the assembly is purely linear are you? The discussion was whether a rib bent and clamped to the rim while bent supports load before it goes negative. Yes, my example is extreme. David Love www.davidlovepianos.com From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On Behalf Of Delwin D Fandrich Sent: Thursday, July 14, 2011 10:55 PM To: pianotech at ptg.org Subject: Re: [pianotech] Measuring Crown Radius No, I was talking about this picture. But as long as were talking about it, where did the data for the graph come from? By actual test? ddf Delwin D Fandrich Piano Design & Fabrication 6939 Foothill Court SW, Olympia, Washington 98512 USA Phone 360.515.0119 - Cell 360.388.6525 del at fandrichpiano.com <mailto:del at fandrichpiano.com> - ddfandrich at gmail.com From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On Behalf Of David Love Sent: Thursday, July 14, 2011 10:30 PM To: pianotech at ptg.org Subject: Re: [pianotech] Measuring Crown Radius Del: Just to clarify my previous post as I sent it from a blackberry. I assume you were talking about this picture. The picture has nothing to do with how the rib is bent. In fact it has nothing to do with *a rib* at all but represents the entire assembly and its deflection characteristics under increasing load. The y axis represents crown and the x axis load. As the load increases the crown diminishes. The crown diminishes at a faster rate as the load is first added, but as the board stiffens with increasing load the rate of deflection per lb diminishes. That's all. cid:image007.png at 01CC376C.19134270 David Love www.davidlovepianos.com -----Original Message----- From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On Behalf Of David Love Sent: Thursday, July 14, 2011 7:26 PM To: pianotech at ptg.org Subject: Re: [pianotech] Measuring Crown Radius It simply illustrates that as load increases the amount of crown diminishes at an ever decreasing rate. David Love www.davidlovepianos.com (sent from bb) -----Original Message----- From: "Delwin D Fandrich" <del at fandrichpiano.com> Sender: pianotech-bounces at ptg.org Date: Thu, 14 Jul 2011 17:09:20 To: <pianotech at ptg.org> Reply-To: pianotech at ptg.org Subject: Re: [pianotech] Measuring Crown Radius David, what are you trying to illustrate in the picture? You have your rib bent to a crown radius that will never be seen in a real piano. ddf Delwin D Fandrich Piano Design & Fabrication 6939 Foothill Court SW, Olympia, Washington 98512 USA Phone 360.515.0119 - Cell 360.388.6525 del at fandrichpiano.com - ddfandrich at gmail.com -------------- next part -------------- An HTML attachment was scrubbed... URL: <https://www.moypiano.com/ptg/pianotech.php/attachments/20110715/0ab6d0df/attachment.htm> -------------- next part -------------- A non-text attachment was scrubbed... Name: not available Type: image/png Size: 787 bytes Desc: not available URL: <https://www.moypiano.com/ptg/pianotech.php/attachments/20110715/0ab6d0df/attachment.png> -------------- next part -------------- A non-text attachment was scrubbed... Name: not available Type: image/png Size: 1932 bytes Desc: not available URL: <https://www.moypiano.com/ptg/pianotech.php/attachments/20110715/0ab6d0df/attachment-0001.png>
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