Return-Path: Received: from relay03.roc.ny.frontiernet.net ([66.133.131.36] verified) by logan.com (CommuniGate Pro SMTP 4.1.8) with ESMTP id 2943749 for flyrotary@lancaironline.net; Thu, 22 Jan 2004 10:15:21 -0500 Received: (qmail 9800 invoked from network); 22 Jan 2004 15:15:19 -0000 Received: from unknown (HELO frontiernet.net) ([170.215.102.232]) (envelope-sender ) by relay03.roc.ny.frontiernet.net (FrontierMTA 2.3.6) with SMTP for ; 22 Jan 2004 15:15:19 -0000 Message-ID: <400FE936.248C7978@frontiernet.net> Date: Thu, 22 Jan 2004 09:16:06 -0600 From: Jim Sower X-Mailer: Mozilla 4.77 [en] (Win98; U) X-Accept-Language: en MIME-Version: 1.0 To: Rotary motors in aircraft Subject: Re: [FlyRotary] Re: Torsionals References: Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Ed, Assuming (key word here) that Tracy's PSRU can be regarded as "tighter tolerances", mightn't rubber bushings effectively "loosen" the tolerances and get us INto more trouble than they get us OUT of? Just wonderin' .... Jim S. Ed Anderson wrote: > Hi Greg, > > Welcome to the list. > > Torsional vibrations and resonance are a fairly complex topic. .. In > generally tighter tolerances raises the resonant frequency of an assembly > and looser tolerances lower it. Tighter tolerances are generally more > expensive than looser. ...By the way, since the rotary does not have a > negative torque region in its > power curve this problem is minimal and can generally be handled by some > simple dampeners such as rubber disks, etc. > > Ed Anderson -- Jim Sower aka Destiny's Plaything ... Crossville, TN; Chapter 5 Long-EZ N83RT, Velocity N4095T