X-CGP-ClamAV-Result: CLEAN X-VirusScanner: Niversoft's CGPClamav Helper v1.23.0 (ClamAV engine v0.103.0) From: "Finn Lassen finn.lassen@verizon.net" Received: from sonic302-22.consmr.mail.ne1.yahoo.com ([66.163.186.148] verified) by logan.com (CommuniGate Pro SMTP 6.2.14) with ESMTPS id 1327086 for flyrotary@lancaironline.net; Fri, 19 Mar 2021 18:16:21 -0400 Received-SPF: pass receiver=logan.com; client-ip=66.163.186.148; envelope-from=finn.lassen@verizon.net DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=verizon.net; s=a2048; t=1616192165; bh=s9EMVJ/2Go/Cl0qwyH5YzC0bTmefMBtKM1v11OpivLw=; h=Subject:To:References:From:Date:In-Reply-To:From:Subject:Reply-To; b=QA1KfN6C9I1m75bNmab1z4Va6KeTkLEuflq6m7wbTIZIkmg2d9rf3TFSt+1TvDil34d7c86B/gwnv79jw9R1VuGxIFKpyCUmGCC2ct1iut1+e56/c5zkGfi/p5bEtFjnuQDWJtIG5jJci+lfrCJIWCzO6hFxlmFD9qrj892NRB8L3UxrMX4m01MlLkxNkWYXAPMX9kzxV9VmB0cxN5CIGzjixUkdIhUhiVstjFI+ns3/ckJP8UfyfGGfLnxuQDGa1+OsvUpXK55+IKPD20UiLI45FR1sRf2vENn1ABg/gh75SPJd6BdTiwE2LUaazRUzuCEA02Ti3BDgeF58EiDRbA== X-SONIC-DKIM-SIGN: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yahoo.com; s=s2048; t=1616192165; bh=ZUKo51JBnc6HTsznvS3aaEAFJain3NwDyRNpeVQdDpu=; h=X-Sonic-MF:Subject:To:From:Date:From:Subject; b=kfZsZ6/LIyYARp7Hp2yfi5AZMTiJ6nwadjZTqfUrFVCfKrAfgA/8X029mJhmZJI6wOboGz0+WQNtLRjVVtS+MO6BMH1995dH7CLMipUB7T9/OJpResDil0NudOnxXcGYaVI5MwRMxZNXSsXyMS0orVQa5DP4JA1xQ0CojGNOVWT+nO0bpDUofqjS5ommIB21s1GGt768JbAsjxW3ag44cJa4bcRsZFooWYRLHZl7IQnPdIf1WaDupmAV7grgC6lMEpWNftsA/DNs2pwYO7OpOAoAjvrLV8DHLemmSWQmuwalbOzul3w2dDvdFrozBCyDIMY7h15eyAlD8Ru8g1Gyqg== X-YMail-OSG: ova178QVM1nNwkFrmE0tTRncIGn6Eb0X8nNhuiuq1Sd4J5yTzTjmmLtAN9EzUVb UCjxkD0YS4kVDUNFR3auxXARZh_hE9uRTlGnOqhsUDus0y785ftsj7h4a90Dqio3r0HO7dErv73X eruvwflvFxz5vhvpVwqb5OPajruHNSW8t0VnpNwIyM0ExqHdmzitLcpB4c7IqKJL6h3EHcGNpJv4 z_J1OsR3moJN0JfOSxngW.rdT9Ns7CfRDIQf2w9g.BWTc1s1lMYzA7b6h0Ultz2Y20EexuQKgwvh gMEn0X9ueGUJkDEM8b9mr8CGykyjDg_VuCjT7_GKQVviRgYDMTjMnEYyW18dTUjCNr.QTj2nJw4u vwGdJkKYjyNrWeBnuZWP5KfuzHmbjffwUZgd2X174aT.3vdGKO.WOjqkYptXLdfAURyPXjl9vxZD SgtrSCi2nR3WnyEiz5JxGxlZLySymevfpyNfzeb8EPfG5558H.Hiwunvcp1hTfJdP0GyZZhfcqvH pv0rxEe1UP_A_y5pcRMLguwF3VZcOrttMrjcCv8yQcwdwL_NMgVZZAc0ifW2tdDMRxu9FuyMNQeB go_jfL7sL5asmikH6FIqF_lSeX.wfCKAulEnYLgqHadt41.x0UbJ13rgWQXmSDOn63k31gzKPVxC fLGGH4FInswLayDp9PYmRnncCgVqb9ajHoJJIWZCE8EhsyF1tlNQwyN7IUX_0EBdXHsBib.1wN8V NBneh91MoNXyo7T5v8NeaFt1wWH8xMANglkbc5ajaOx_TbujfDc4Ic_drzjYCuKh.3PIKIne3xdm 00_Z9srAoQwjwbGhwLiu01gxN1SyssVAchs82Peoho4TTyuQAzaiOxhn8haOhTek7AKBdmto5wVN S1PaFBo.kb0jeAiCIDLuJH6eKPqOVmS_40Dil15Wac44oLoDJZTe2v9.euST7uOJtLNOpg8_1xhF Vb2HjrsC1Ghhok0rEo53OMAp619.P76fLr4.oyN7jka.4YVKp1ow2dDu_ZLY2igNJ0GkeigtiFLJ u5PsQ4YG6F70HBDQ3L6lUpR_2mLpnc8oQIPLH49DpbH.f2Cp5r9YwRyPG4Ybkf4x3JgAK6Fbz7gb Ii7f2L7QbBrIRgMI7cX0pvUwafHSJgQWj2n2qdFhLmMStGLx.H.ANrvLd.yT8qyceRywtZbl4PuG 7aigbnnci7UtKK9Fx3p5k_MQolEOh38CDXsxZCdK_WjqozVKYkFTjANBxMwh7pbFyDQKSwnqNWc5 p8XMHGT7ihhTSgsZPQs.q7Pzq3V2g9Z3yH1ajmkZRQQPDghCU2MCLPZOw.jAtxH.K8JZhOio7VQB qteSZBBB.pvAwGKErc4LUO83gPQBYl_xF.xQ.vKSNvl52r9s.Krxgtro0ulZ4jk87_.rh4stECgz sQGzvaHi2c0_301s0qdgqhHBB4I2yCDL4WMrdM0HhYgzNcBRvJqFPPf4Kz7YI.fCyA1uOxnpe2El KUHyjMaeTvI8MfnkfM6r0JSx3_La7sieN3ESoJJZEeXXnAfkkxaFDAagPA5RC59uhlINo4bKc66a z5Ai1rKrR5ZlJHE7.4jEtvwqH9uGkDf2aWbiTWYBUY7B3J29kfa7Zjmfj8cnrd.XdXgCqjBP.Qpp vgiG.K6u6IPa2hXRjx4L039xEzZ15BPCdmEjnOje9mfwc5Ccwvo3tYBNcVN0kykrF3WIw6ZTGnEz jicOXZKUALMEUzlMZF4VcSH0RZ9zfl9NCZs1zxdOkfaEkKgSWVZZ2KzkS8.TuuBiKiQsBZL53TNE _91oCHgyuB9jmTTMdbJzAkijOpuXNYdZO5IFqWCGWsgIlEnqYl1B8yq3.shAM_GsaQW00yv6AwgO NeoLcX_STF3y0KOSL6hVgD4VT0o0zzvtKiIkZJbHR34Egl9rHpROWm8MLHqv2XvxUoIAEPjmkK8s OVEQMWuzvqWJvUevOLlfg81UCnlROIkrR4bajUFYQ0mS8UE8_GeZLV9rlxnFBk4VUKzEM7S5t3Rq 48Cp.xBHaYpSwLOuvkpKUNWazpFxdQDi2vucE6yAHLG2ZrY42Ua2.Aggep.NuXPqNujvhJyh3bed NDiAfypThAAqyjdaryybn7PsHqAeKCCYcv_OYgWA3Jqst9wKFBv37A60cOgrE66qgiSLjvz2VYy4 7Qm5qlNkfu.6EqawfvGDHBKricMBIK.0PaCr2tnz3vCw8F2eHNKK8hiTIhX8jIFLrgDmqWD85g9g cX3gUF7UClb0oRo0.G9AI5IOjsO9YSKVdaHPVvPmOEjoDPoW9lvFv8VoOuxfauTMwz0eysHNIIS0 M8M6P8Jv0nGnk6R4qnfBBtJeBsRTVwfzYp5ALFEq.XWmrnv05Apys3fJ.keqPTgDXdhrzNKrXhp2 Bqcdxmmo- X-Sonic-MF: Received: from sonic.gate.mail.ne1.yahoo.com by sonic302.consmr.mail.ne1.yahoo.com with HTTP; Fri, 19 Mar 2021 22:16:05 +0000 Received: by smtp421.mail.bf1.yahoo.com (VZM Hermes SMTP Server) with ESMTPA ID 8155c24380303ddaccee5d6af3e4de5f; Fri, 19 Mar 2021 22:16:00 +0000 (UTC) Subject: Re: [FlyRotary] Re: dynamic balance To: Rotary motors in aircraft References: Message-ID: Date: Fri, 19 Mar 2021 18:15:57 -0400 User-Agent: Mozilla/5.0 (Windows NT 5.1; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Content-Language: en-US X-Antivirus: Avast (VPS 210319-4, 03/19/2021), Outbound message X-Antivirus-Status: Clean X-Mailer: WebService/1.1.17936 mail.backend.jedi.jws.acl:role.jedi.acl.token.atz.jws.hermes.aol Apache-HttpAsyncClient/4.1.4 (Java/11.0.9.1) Content-Length: 1657 Thanks Steve. That really helps! Didn't even think about the flex plate. Might try to remove that when I remove the PSRU to replace oil seal. Tracy also mentioned rotor and counter weights imbalances and thinks that can't really compensate for those with a weight on the flywheel. So the combustion event theory is dead. Finn On 3/19/2021 4:26 PM, Sboese sboese@uwyo.edu wrote: > Finn, > > The FFT processing required two channels recorded simultaneously, one > for the position reference and one for the accelerometer. > > The system I used allowed sampling of each channel at 5khz with no > external amplification or filtering. > > My guess as to the prop 3x(blade) signal is that it is an interaction > with the ground.  The prop is 76” dia resulting in about 8” of prop > tip to ground clearance. > > Also a guess on my part is that the engine 1x vibration may be coming > from the flex plate shifting on the rubber dampers.  My system has > about 0.020” of clearance between the corners of the damper plate and > the flex plate rim when centered.  When attempting to balance the > engine, a point was reached where no further improvement was made and > the phase angle was not consistent between tests.  I don’t know how > much the splined shaft can restrict the possible shift off center of > the damper plate, but the intensity of the vibration was consistent > with the weight of the damper plate and 0.020” of eccentricity.  This > may also be affected by the load on the rubber dampers. > > Steve Boese > --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus