X-Junk-Score: 0 [] X-KAS-Score: 0 [] From: "Charlie England ceengland7@gmail.com" Received: from pmg.Logan.com ([207.170.160.161] verified) by logan.com (CommuniGate Pro SMTP 6.4.0) with ESMTPS id 3786945 for flyrotary@lancaironline.net; Mon, 13 Jan 2025 12:37:28 -0500 Received: from pmg.Logan.com (localhost [127.0.0.1]) by pmg.Logan.com (Proxmox) with ESMTP id BDA15F921 for ; Mon, 13 Jan 2025 12:37:28 -0500 (EST) Received-SPF: pass (gmail.com ... _spf.google.com: Sender is authorized to use 'ceengland7@gmail.com' in 'mfrom' identity (mechanism 'include:_netblocks.google.com' matched)) receiver=pmg.Logan.com; identity=mailfrom; envelope-from="ceengland7@gmail.com"; helo=mail-ed1-f52.google.com; client-ip=209.85.208.52 Received: from mail-ed1-f52.google.com (mail-ed1-f52.google.com [209.85.208.52]) by pmg.Logan.com (Proxmox) with ESMTPS for ; Mon, 13 Jan 2025 12:37:28 -0500 (EST) Received: by mail-ed1-f52.google.com with SMTP id 4fb4d7f45d1cf-5d3e9a88793so7669625a12.1 for ; Mon, 13 Jan 2025 09:37:28 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1736789840; x=1737394640; darn=lancaironline.net; h=to:subject:message-id:date:from:in-reply-to:references:mime-version :from:to:cc:subject:date:message-id:reply-to; bh=dSFSgMjcQIiyHT9TOw3AACwJl2w8wXzCt8yJqDnaBhg=; b=I5Mwtutz3quglmzGTjG5yhfDgN3mRKTSG6vSSzejO8snmULxExmbxCiqLzsxuFDDzT 5FOPACp1AGQLE+pNbcC9UFzjwDNUOsFCOL/Cv1UUjPDiVMG/yxUPQJErB4bNn3w4HylD kGVFeYtjOwIctyirmt56I24YqHaGi2J/3fGuW1KUQgHNxmcqojq51CFHRG1c0rdKFLXu FLWDNDgZkFJy/LVBXTdqr8sZWDnZV7/+B4XwiWQ8WcT3+CosoyiQf9UKLuQ3t7VmQr1L HaJoclaVbcFZMDzdeYZhvN6j3ljFhYJ9WVGGk17UZBCfEkJtzRW3VTQARJSEfP7i3jtn PYgg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1736789840; x=1737394640; h=to:subject:message-id:date:from:in-reply-to:references:mime-version :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=dSFSgMjcQIiyHT9TOw3AACwJl2w8wXzCt8yJqDnaBhg=; b=F3Cqin9N8HFQK4nucHIqnEB+fjdANRqIs5FduXhgIMO+ZaZGgKGikau4VqeoPM97e1 ahHXNoOQnATsTC6MGi6vdoQBEV3nqn/DxlMsDWOiPPj8Sf8FGeXHIiSm9raXtphXEWGi qkE661/LC8KjsauJz4CffR5PxOIvtV8QCicGCRtcLXYCL/q9RFrbQDL4mbr9YeIfN0Bk 8hcTPL56Qgyu8YaGLDottaQxn5AwqFiQQ8iEViJoC3u0iAUyTkRVZ6K+SzlpP9pG0E+Z +N7jNMqfILyQo965uaBTdofY0TNqU/wg+RllOvFznySjTA9BCYbr5Y83ONuHiSRMgX9U 4uQQ== X-Gm-Message-State: AOJu0YxChUQpfqvrfLlUzLGxJ2HvD41mOp2fGJ1ffpcdNhrKwqBsSFLx V+fzEDGbzUnttPX0L9MTJqDCV4yGCZt87dnbyqqkOoiFe1hCemeSrX34ijdj7g4vZECZlFWdX65 HFdbAIFOhtIegZA26C6ZfQSoRbl+IPA== X-Gm-Gg: ASbGncsyB1spC8mDXAl9aPylNsuopvZfULB/Pfz8YmDSWgvxnKiievOvn7NpXi7llSp O+2ivNjWoPXcrNESyk8pUOTCk7YzIwUMlZssw X-Google-Smtp-Source: AGHT+IE3tmBYxleVISSPyHyPhJZiyOBdci/8ejY4wr6u7i+MvQyNgj5Y8WyHqEHPaOCOaDCStEPG/j+XJwuw16IbFoE= X-Received: by 2002:a05:6402:518f:b0:5d0:abb8:79d with SMTP id 4fb4d7f45d1cf-5d972e083f9mr12184817a12.14.1736789839968; Mon, 13 Jan 2025 09:37:19 -0800 (PST) MIME-Version: 1.0 References: In-Reply-To: Date: Mon, 13 Jan 2025 11:37:08 -0600 X-Gm-Features: AbW1kvYVaXFArwWcvdhFk5pnjCJ8fMQ0R8L_orxG3LViA0xSrwWnPUwtE7_jIVs Message-ID: Subject: Re: [FlyRotary] Re: Flexplate cracks To: Rotary motors in aircraft Content-Type: multipart/alternative; boundary="000000000000762959062b99e575" X-SPAM-LEVEL: Spam detection results: 0 AWL 1.761 Adjusted score from AWL reputation of From: address BAYES_00 -1.9 Bayes spam probability is 0 to 1% DKIM_SIGNED 0.1 Message has a DKIM or DK signature, not necessarily valid DKIM_VALID -0.1 Message has at least one valid DKIM or DK signature DKIM_VALID_AU -0.1 Message has a valid DKIM or DK signature from author's domain DKIM_VALID_EF -0.1 Message has a valid DKIM or DK signature from envelope-from domain DMARC_PASS -0.1 DMARC pass policy FREEMAIL_ENVFROM_END_DIGIT 0.25 Envelope-from freemail username ends in digit FREEMAIL_FROM 0.001 Sender email is commonly abused enduser mail provider HTML_MESSAGE 0.001 HTML included in message RCVD_IN_MSPIKE_H2 -1.787 Average reputation (+2) SPF_HELO_NONE 0.001 SPF: HELO does not publish an SPF Record SPF_PASS -0.001 SPF: sender matches SPF record T_REMOTE_IMAGE 0.01 Message contains an external image --000000000000762959062b99e575 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Hmmm; starting to look like a plan. 3/16" could be steel, to add rotating mass and strength for less money. ;-) Charlie On Mon, Jan 13, 2025 at 1:34=E2=80=AFAM Steven W. Boese SBoese@uwyo.edu < flyrotary@lancaironline.net> wrote: > Charlie, > > A 3/16=E2=80=9D thick disc would place the female spline in the original = position > and would most likely stabilize the Flexplate greatly. An accurately > machined hole in the center would engage the hub of the splined part and > still allow that hub to protrude enough to engage the spacer. In that wa= y, > one would not be depending on the bolts to maintain alignment. > > Steve Boese > > On Jan 12, 2025, at 2:53=E2=80=AFPM, Charlie England ceengland7@gmail.com= < > flyrotary@lancaironline.net> wrote: > > =EF=BB=BF > > =E2=97=86 This message was sent from a non-UWYO address. Please exercise = caution > when clicking links or opening attachments from external sources. > > Thanks for those images. Looks like a larger AL disc could replace part o= f > the spacer's thickness and bolt to the holes where the damper plate > mounted. Does that look reasonable 'in person'? > > If feasible, I'm thinking that it could serve two purposes; raise resonan= t > freq of the flexplate to a safe area, and add mass close to what would be > in an AL flywheel (they're getting hard to find used, and new ones are > really expensive). > > I suspect the extra rotating mass on the Eshaft is needed (or at least a > good idea). > > Charlie > > > > Virus-free.www.avast.com > > <#m_-1607297480231373792_DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2> > > On Sat, Jan 11, 2025 at 6:45=E2=80=AFPM Steven W. Boese SBoese@uwyo.edu < > flyrotary@lancaironline.net> wrote: > >> When the Flexplate is bolted to the eccentric shaft without the damper >> plate it rings with frequencies of around 320 and 1340 Hz. It doesn=E2= =80=99t ring >> with the damper attached. >> This gives the possibility that the Flexplate without the damper may >> resonate being excited by the engine harmonics at rpm ranges normally us= ed >> in flight. Such resonance could accelerate Flexplate cracking. For thi= s >> reason, I would be reluctant to eliminate the damper while retaining the >> Flexplate. Converting to Tracy=E2=80=99s recent solid coupling design m= ay best be >> done by also replacing the Flexplate with a manual transmission flywheel= . >> >> The photo shows a couple of possibilities to convert to a solid coupling >> while retaining the original splined input shaft. The thickness of the >> aluminum spacer or the steel part can be adjusted to accommodate the >> thickness of a flywheel. >> >> Steve Boese >> >> >> >> --000000000000762959062b99e575 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
Hmmm; starting=C2=A0to look like a plan. 3/16" could be = steel, to add rotating mass and strength for less money. ;-)

Charlie

On M= on, Jan 13, 2025 at 1:34=E2=80=AFAM Steven W. Boese SBoese@uwyo.edu <flyrotary@lancaironline.net> wrote:
Charlie,

A 3/16=E2=80=9D thick disc would place the female spline i= n the original position and would most likely stabilize the Flexplate great= ly.=C2=A0 An accurately machined hole in the center would engage the hub of= the splined part and still allow that hub to protrude enough to engage the spacer.=C2=A0 In that way, one would not be depending= on the bolts to maintain alignment.

Steve Boese=C2=A0

On Jan 12, 2025, at 2:53=E2=80=AFPM, Charlie Engl= and ceengland7@gm= ail.com <flyrotary@lancaironline.net> wrote:

=EF=BB=BF

=E2=97=86 This message= was sent from a non-UWYO address. Please exercise caution when clicking li= nks or opening attachments from external sources.


Thanks for those images. Looks like a larger= AL disc could replace part of the spacer's thickness and bolt to the h= oles where the damper plate mounted. Does that look reasonable 'in pers= on'?

If feasible, I'm thinking that it could = serve two purposes; raise resonant freq of the flexplate to a safe area, an= d add mass close to what would be in an AL flywheel (they're getting ha= rd to find used, and new ones are really expensive).

I suspect the extra rotating mass on the Esh= aft is needed (or at least a good idea).=C2=A0

Charlie

3D"" Virus-free.www.avast.com

On Sat, Jan 11, 2025 at 6:45=E2=80=AF= PM Steven W. Boese SBoese@uwyo.edu &l= t;flyrotar= y@lancaironline.net> wrote:
When the Flexplate is bolted to the eccentric shaft witho= ut the damper plate it rings with frequencies of around 320 and 1340 Hz.=C2= =A0 It doesn=E2=80=99t ring with the damper attached.
This gives the possibility that the Flexplate without the damper may r= esonate being excited by the engine harmonics at rpm ranges normally used i= n flight.=C2=A0 Such resonance could accelerate Flexplate cracking.=C2=A0 F= or this reason, I would be reluctant to eliminate the damper while retaining the Flexplate.=C2=A0 Converting to Tracy=E2=80= =99s recent solid coupling design may best be done by also replacing the Fl= explate with a manual transmission flywheel.

The photo shows a couple of possibilities to convert to a solid coupli= ng while retaining the original splined input shaft.=C2=A0 The thickness of= the aluminum spacer or the steel part can be adjusted to accommodate the t= hickness of a flywheel.

Steve Boese=C2=A0

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