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 3784918 for flyrotary@lancaironline.net; Sat, 11 Jan 2025 16:11:51 -0500 Received: from pmg.Logan.com (localhost [127.0.0.1]) by pmg.Logan.com (Proxmox) with ESMTP id 265F433944 for ; Sat, 11 Jan 2025 16:11:51 -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-f44.google.com; client-ip=209.85.208.44 Received: from mail-ed1-f44.google.com (mail-ed1-f44.google.com [209.85.208.44]) by pmg.Logan.com (Proxmox) with ESMTPS for ; Sat, 11 Jan 2025 16:11:50 -0500 (EST) Received: by mail-ed1-f44.google.com with SMTP id 4fb4d7f45d1cf-5d122cf8e52so5151713a12.1 for ; Sat, 11 Jan 2025 13:11:50 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1736629902; x=1737234702; 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=kylbCShqYDTZMoylnxhPXLST8pTOs5PLTpmNcFQcsRY=; b=i/kmPsLnica7EEC7j0bKLMVhD63UsskfSlFVwmjtSowOeocisH0tnPM6ly7j+U0HKU Nv/4n4xR0jRWWlYqfGUdwTLUJ5efl3KnQQmotesV0G4iLQ0r94mFa7zZMp2YYaQsziSS YlUaDv0i36xHcoT1qoA3uVyLV60w4HB+lhEakCJTTsXTfM3APrXZB7pNfmuMnhH9PZul 4P2HkZXB96kz4MF9Z/A2cIzHE7q/UBNMLDYuxa0wEK6F7RorkrdXdq1ii0LzRl6aaonG n7jbVREEsBoe4VzRo3iN7CyzPQLhmzsks1shB+ZsmJZKv6tIJlPhkHJ5bHf4CqjtEwlU 1mRQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1736629902; x=1737234702; 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=kylbCShqYDTZMoylnxhPXLST8pTOs5PLTpmNcFQcsRY=; b=WwnAt2jQK5zWnyemFT1pKcmKBKo/8PbpV50o/YHWAHjjREL8l7eYpsTivnF2W95T/4 bvt7RNg7c6p3w+yjqDL5bAgONT+95opZzd3qcB7oLyFW4dENGI0ZCDwTR6tsQM4GbFdW XjlY1RNCzVoljgJLO+538hb5WviP05xtZwOQUfHTR974+8HP0nXGuqMmTxQ99SAMBkJV 4mJMnkJJCo2e312xBwguwA0YEf9OLBsO5q2xTchyySDURS0AQLoi8LKHc6rUs//nC7U9 HjziJBYvdsLp82x+nuAtjCEWIh0SQFEo/y9Vr/8HqRXDJPhGzIP6aX93scjLhG5RRGtt hAeA== X-Gm-Message-State: AOJu0YzBj1Y+FIrT1tqWPNEefmJfaICw+qSwDa0ZtubFvs4eELRLJys5 BMUGwK33IdI/D1epjMAN1cPFXkdOEkCrSCs69pVaC2l+QCGsZnY3mpAhT+pirv73MPkQrpvjRXo bO6SgLk3NaDwN48BJ4ZC+ry915BLVEw== X-Gm-Gg: ASbGncup3FkRU7VzRDGRuKaJk+nw39ApUJbB1U435HPTCgSC1S6j470nBGPKT+Enes7 ghjCpFjhl5Hq03v1H3XN77+xFyWiUof4IEpoe X-Google-Smtp-Source: AGHT+IF2gzpZDZDNCnpBi1DFnq0XD9C4EzTkVelgXkNaQ9Lpp6IiV01+UngeBluaH0Q9tWFLszfTPCnTiLfmF1fG8cw= X-Received: by 2002:a05:6402:430c:b0:5d4:75b:8ced with SMTP id 4fb4d7f45d1cf-5d972e6bdf5mr14491225a12.32.1736629902343; Sat, 11 Jan 2025 13:11:42 -0800 (PST) MIME-Version: 1.0 References: In-Reply-To: Date: Sat, 11 Jan 2025 15:11:31 -0600 X-Gm-Features: AbW1kvZSHC-rezGDVnUqIIZtkx3pHCHM8-ssqejuikblPVK_BFiiYUa5blKq3gM Message-ID: Subject: Re: [FlyRotary] Re: Flexplate cracks To: Rotary motors in aircraft Content-Type: multipart/alternative; boundary="0000000000006f84c3062b74a8d6" X-SPAM-LEVEL: Spam detection results: 0 AWL -0.837 Adjusted score from AWL reputation of From: address BAYES_00 -1.9 Bayes spam probability is 0 to 1% CBJ_GiveMeABreak 1.75 Messages with consecutive break characters 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 KAM_MXURI 1.5 URI begins with a mail exchange prefix, i.e. mx.[...] RCVD_IN_MSPIKE_H2 -0.001 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 WEIRD_PORT 0.001 Uses non-standard port number for HTTP --0000000000006f84c3062b74a8d6 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable What does the torque converter bolt to? I thought they bolted to the holes Tracy uses for the 'damper' puck bolts. Virus-free.www.avast.com <#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2> On Sat, Jan 11, 2025 at 1:45=E2=80=AFPM David Leonard wdleonard@gmail.com < flyrotary@lancaironline.net> wrote: > The counterweight is connected to the eshaft with a key. Then the flex > plate bolts directly to the counterweight > > On Fri, Jan 10, 2025, 8:36 PM Stephen Izett stephen.izett@gmail.com < > flyrotary@lancaironline.net> wrote: > >> Hi there Dave >> >> I understood the torque converter was driven from the flex plate. >> Can someone confirm how power is transferred from the Eccentric to the >> torque converter? >> >> Steve Izett >> >> On 11 Jan 2025, at 9:35=E2=80=AFam, David Leonard wdleonard@gmail.com < >> flyrotary@lancaironline.net> wrote: >> >> in the car, the flex plates are only used to carry the torque from the >> starter and are not designed to transmit the output of the engine. in ou= r >> setups. We have adapted this flex plate to transmit the entire output of >> the engine which it apparently is not up to. >> >> I had my rd1-b seize up a bearing during a race at Reno which may have >> been due to gyroscopic forces, but I think the flex plate issue just nee= ds >> to be fixed by replacing all the flex plates with proper flywheels. >> >> Dave Leonard >> >> On Fri, Jan 10, 2025, 1:45=E2=80=AFAM Le Roux Breytenbach >> breytenbachleroux@gmail.com wrote: >> >>> What i can rember was this also a topic on the late Paul L group >>> discussion. >>> Maybe Dave Leonard can chime in - think more that it was gyroscopic >>> forces that craked the plates >>> Maybe i can find the photos and topic in my old mails >>> >>> Sent from my iPhone >>> Le Roux Breytenbach >>> >>> On 10 Jan 2025, at 08:13, Andrew Martin andrew@martinag.com.au < >>> flyrotary@lancaironline.net> wrote: >>> >>> =EF=BB=BF >>> Maybe some of the cracking flexplates are resulting from starting >>> issues, the starter motor can hammer the ring gear if not meshing corre= ctly >>> or if engine misfires on start. may explain why so many flexplates come >>> pre-cracked from the wreckers. >>> >>> Andrew >>> >>> >>> >>> >>> >>> On Fri, 10 Jan 2025 at 11:32, Stephen Izett stephen.izett@gmail.com < >>> flyrotary@lancaironline.net> wrote: >>> >>>> Hi M >>>> >>>> I was wondering the same thing. >>>> >>>> What I discovered first of all was that flex plates are designed to >>>> flex (funny that) and cracking is not limited to our setup. >>>> There are companies that specialise in stronger flex plates, >>>> particularly for modified and higher horsepower engines. >>>> >>>> Since our engines are being used at a higher horsepower per unit time >>>> and therefore higher stress (assumption) perhaps our setup could be li= kened >>>> to race applications. >>>> But then our hours of use would be significantly lower (assumption) >>>> than an average vehicle, but perhaps not a race application. >>>> Is the cracking we are seeing consistent with race applications? But >>>> they dont race automatics, do they? >>>> >>>> So my take on this is that perhaps the flexing of the plate in our >>>> setup is to some extent higher than OEM. >>>> >>>> Our options seem to be: >>>> 1. Replacing the OEM flex plate with a stronger part. Steve B being th= e >>>> latest going down that track and in his case also removing the rubber >>>> isolation in the process. >>>> 2. Connect direct to the eccentric shaft and therefore taking the >>>> stress off the Flex Plate doing away with the damping mechanism which = Tracy >>>> did, and perhaps is still doing. Would be real nice to know. >>>> >>>> Like M, I would appreciate hearing what others know or are thinking or >>>> doing. >>>> >>>> Steve Izett >>>> >>>> >>>> >>>> >>>> >>>> >>>> >>>> >>>> >>>> >>>> >>>> >>>> > On 10 Jan 2025, at 2:15=E2=80=AFam, Marc Wiese cardmarc@charter.net = < >>>> flyrotary@lancaironline.net> wrote: >>>> > >>>> > Has the cause of these cracks been uncovered, and if so, what is the >>>> current thinking on it? An AL racing plate? >>>> > M >>>> > Sent from my iPhone >>>> > >>>> >> On Jan 9, 2025, at 1:31=E2=80=AFAM, Steven W. Boese SBoese@uwyo.edu= < >>>> flyrotary@lancaironline.net> wrote: >>>> >> >>>> >> =EF=BB=BFSteve, >>>> >> >>>> >> I didn=E2=80=99t see the cracks prior to disassembly and doubt that= they >>>> could have been seen on the counterweight side very well -if at all- w= hen >>>> assembled. >>>> >> >>>> >> I replaced the Flexplate with a steel flywheel about a year ago. >>>> Since then, I replaced the four rubber dampers with machined aluminum = discs >>>> giving a solid connection and then dynamically balanced the system. T= his >>>> was done because maintaining a dynamic balance wasn=E2=80=99t possible= with the >>>> dampers. Only a few hours of flight have occurred in this configurati= on so >>>> far and there has been no indication of problems resulting from this c= hange. >>>> >> >>>> >> Steve Boese >>>> >> >>>> >>> On Jan 8, 2025, at 11:03=E2=80=AFPM, Stephen Izett stephen.izett@g= mail.com >>>> 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 sourc= es. >>>> >>> >>>> >>> >>>> >>> Hi Steve >>>> >>> >>>> >>> Is this recent then? >>>> >>> >>>> >>> I=E2=80=99m not able to get to my aircraft at present to check my = flex >>>> plate which has probably seen 50 hours of service. >>>> >>> >>>> >>> Was it possible to see these cracks assembled? >>>> >>> >>>> >>> I would appreciate your reflections on Tracys latter choice to >>>> remove the damper, and particularly when using a timber/glass prop suc= h as >>>> an MT. >>>> >>> >>>> >>> It would be great to have an update and current info from Tracy >>>> regarding his no damper hours if anyone can contact him. >>>> >>> >>>> >>> Very helpful, thanks again Steve >>>> >>> >>>> >>> Steve >>>> >> >>>> >> -- >>>> >> Homepage: http://www.flyrotary.com/ >>>> >> Archive and UnSub: >>>> http://mail.lancaironline.net:81/lists/flyrotary/List.html >>>> > >>>> > >>>> > >>>> > -- >>>> > Homepage: http://www.flyrotary.com/ >>>> > Archive and UnSub: >>>> http://mail.lancaironline.net:81/lists/flyrotary/List.html >>>> >>>> >>>> >>>> -- >>>> Homepage: http://www.flyrotary.com/ >>>> Archive and UnSub: >>>> http://mail.lancaironline.net:81/lists/flyrotary/List.html >>>> >>> >> --0000000000006f84c3062b74a8d6 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
Wha= t does the torque converter=C2=A0bolt to? I thought they bolted to the hole= s Tracy uses for the 'damper' puck bolts.

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

On Sat, Jan 11, 2025 at 1:45= =E2=80=AFPM David Leonard wdleonard@= gmail.com <flyrotary@= lancaironline.net> wrote:
The counterweight is connected to the es= haft with a key. Then the flex plate bolts directly to the counterweight
On = Fri, Jan 10, 2025, 8:36 PM Stephen Izett stephen.izett@gmail.com <flyrotary@lancaironline.ne= t> wrote:
Hi there Dave

I understood the torque converter wa= s driven from the flex plate.=C2=A0
Can someone confirm how power= is transferred from the Eccentric to the torque converter?

<= /div>
Steve Izett

On 11= Jan 2025, at 9:35=E2=80=AFam, David Leonard wdleonard@gmail.com <<= a href=3D"mailto:flyrotary@lancaironline.net" rel=3D"noreferrer" target=3D"= _blank">flyrotary@lancaironline.net> wrote:

in the car, the flex plates are only used to carry the torque fro= m the starter and are not designed to transmit the output of the engine. in= our setups. We have adapted this flex plate to transmit the entire output = of the engine which it apparently is not up to.=C2=A0

=
I had my rd1-b seize up a bearing during a race at = Reno which may have been due to gyroscopic forces, but I think the flex pla= te issue just needs to be fixed by replacing all the flex plates with prope= r flywheels.=C2=A0

Dave = Leonard=C2=A0

On Fri, Jan 10, 2025, 1:45=E2=80=AFAM Le Roux Breytenbac= h breytenbachleroux@gmail.com <flyrotary@lancairo= nline.net> wrote:
What i can rember was this also a topic on the= late Paul L group discussion.
Maybe Dave Leonard can chime in - think = more that it was gyroscopic forces that craked the plates
Maybe i= can find the photos and topic in my old mails

Sent from my iPhone
Le Roux Breytenbach= =C2=A0

On 10 Jan = 2025, at 08:13, Andrew Martin andrew@martinag.com.au <= ;flyrotary@lancaironline.net> wrote:

=EF=BB=BF
Maybe some of the cracking flexplates are resulting from star= ting issues, the starter motor can hammer the ring gear if not meshing corr= ectly or if engine misfires on start. may explain why so many flexplates co= me pre-cracked from the wreckers.

Andrew





On Fri, 10 Jan 2025 = at 11:32, Stephen Izett stephen.izett@gmail.com <flyrotary@lancaironline.net> wrote:
Hi M

I was wondering the same thing.

What I discovered first of all was that flex plates are designed to flex (f= unny that) and cracking is not limited to our setup.
There are companies that specialise in stronger flex plates, particularly f= or modified and higher horsepower engines.

Since our engines are being used at a higher horsepower per unit time and t= herefore higher stress (assumption) perhaps our setup could be likened to r= ace applications.
But then our hours of use would be significantly lower (assumption) than an= average vehicle, but perhaps not a race application.
Is the cracking we are seeing consistent with race applications? But they d= ont race automatics, do they?

So my take on this is that perhaps the flexing of the plate in our setup is= to some extent higher than OEM.

Our options seem to be:
1. Replacing the OEM flex plate with a stronger part. Steve B being the lat= est going down that track and in his case also removing the rubber isolatio= n in the process.
2. Connect direct to the eccentric shaft and therefore taking the stress of= f the Flex Plate doing away with the damping mechanism which Tracy did, and= perhaps is still doing. Would be real nice to know.

Like M, I would appreciate hearing what others know or are thinking or doin= g.

Steve Izett












> On 10 Jan 2025, at 2:15=E2=80=AFam, Marc Wiese cardmarc@c= harter.net <flyrotary@lancaironline.net> = wrote:
>
> Has the cause of these cracks been uncovered, and if so, what is the c= urrent thinking on it? An AL racing plate?
> M
> Sent from my iPhone
>
>> On Jan 9, 2025, at 1:31=E2=80=AFAM, Steven W. Boese SBoese= @uwyo.edu <flyrotary@lancaironline.net> w= rote:
>>
>> =EF=BB=BFSteve,
>>
>> I didn=E2=80=99t see the cracks prior to disassembly and doubt tha= t they could have been seen on the counterweight side very well -if at all-= when assembled.
>>
>> I replaced the Flexplate with a steel flywheel about a year ago.= =C2=A0 Since then, I replaced the four rubber dampers with machined aluminu= m discs giving a solid connection and then dynamically balanced the system.= =C2=A0 This was done because maintaining a dynamic balance wasn=E2=80=99t p= ossible with the dampers.=C2=A0 Only a few hours of flight have occurred in= this configuration so far and there has been no indication of problems res= ulting from this change.
>>
>> Steve Boese
>>
>>> On Jan 8, 2025, at 11:03=E2=80=AFPM, Stephen Izett stephen.izett@gmail.com <flyrotary@lancairo= nline.net> wrote:
>>>
>>> =EF=BB=BF=E2=97=86 This message was sent from a non-UWYO addre= ss. Please exercise caution when clicking links or opening attachments from= external sources.
>>>
>>>
>>> Hi Steve
>>>
>>> Is this recent then?
>>>
>>> I=E2=80=99m not able to get to my aircraft at present to check= my flex plate which has probably seen 50 hours of service.
>>>
>>> Was it possible to see these cracks assembled?
>>>
>>> I would appreciate your reflections on Tracys latter choice to= remove the damper, and particularly when using a timber/glass prop such as= an MT.
>>>
>>> It would be great to have an update and current info from Trac= y regarding his no damper hours if anyone can contact him.
>>>
>>> Very helpful, thanks again Steve
>>>
>>> Steve
>>
>> --
>> Homepage:=C2=A0 http://www.flyrotary.com/
>> Archive and UnSub:=C2=A0 =C2=A0http://mail.lancaironline.net:81/lists/flyrotary/List.h= tml
>
>
>
> --
> Homepage:=C2=A0 http://www.flyrotary.com/ > Archive and UnSub:=C2=A0 =C2=A0http://mail.lancaironline.net:81/lists/flyrotary/List.html<= /a>



--
Homepage:=C2=A0 http://www.flyrotary.com/
Archive and UnSub:=C2=A0 =C2=A0http://mail.lancaironline.net:81/lists/flyrotary/List.html<= br>

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