X-Junk-Score: 0 [] X-Cloudmark-Score: 0 [] X-Cloudmark-Analysis: v=2.2 cv=UschDK4B c=1 sm=1 tr=0 a=T3HAWIOdjWoca81rNQcl3g==:117 a=7ZeHUF5TpD32QnDE67vapA==:17 a=x7bEGLp0ZPQA:10 a=A-0mRrAPPO4A:10 a=JHtHm7312UAA:10 a=r77TgQKjGQsHNAKrUKIA:9 a=3oc9M9_CAAAA:8 a=Ia-xEzejAAAA:8 a=1XWaLZrsAAAA:8 a=pGLkceISAAAA:8 a=o2QoyYduAAAA:8 a=_6GpL_ENAAAA:8 a=AYVOKvsbuQmZSjg6iAAA:9 a=QEXdDO2ut3YA:10 a=4PR2P7QzAAAA:8 a=txlBB-isFlqFoNghBKUA:9 a=uhlSz-Q3PiokT20S:21 a=_W_S_7VecoQA:10 a=Urk15JJjZg1Xo0ryW_k8:22 a=S50rnUa8yRbNnh2hyxzf:22 a=4dqwQCo7Po2mVW515mGf:22 From: "Charlie England ceengland7@gmail.com" Received: from mail-yw1-f46.google.com ([209.85.161.46] verified) by logan.com (CommuniGate Pro SMTP 6.2.9) with ESMTPS id 11832919 for flyrotary@lancaironline.net; Thu, 01 Nov 2018 14:30:27 -0400 Received-SPF: pass receiver=logan.com; client-ip=209.85.161.46; envelope-from=ceengland7@gmail.com Received: by mail-yw1-f46.google.com with SMTP id j202-v6so8276477ywa.13 for ; Thu, 01 Nov 2018 11:30:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:references:from:message-id:date:user-agent:mime-version :in-reply-to:content-language; bh=iXatJcGb4slTF0mp+U5gp1Ph/CD9xoIiG15gAKcKhB4=; b=NEEgolOzH5gGCLqV5SJ3mes8K+1AZEFSkxARFDLVD7489BEZAMkQe2LzfdlG0Pi4l2 t610hdbFfVPpaVegORYKq5wEqlEKwzmp+0ep8xMLqx1Gstz0zxw4RV14bzoCRT9Wf4BU 4/FUJn88Ets3qe9A9Nyum/lyPjcwA/yz/iurOQC351rWPkXENU4cgsYedUMbqxwakSUn EQu6oOk9CzOd4F0QgoZzUcRVb0r8kH/p04CRCI9KZCmYBqwN+bhxy3ncYSzGHZNUtB2H zDVD1ysGESEGt/wp5DhLWH1t64Fl1uhQfUNPBu7QIoC54ZN/6aNlSFXJRyw38zCTda9W Ef5g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language; bh=iXatJcGb4slTF0mp+U5gp1Ph/CD9xoIiG15gAKcKhB4=; b=rvp0ujWM+C0ydTC18Ihz6Vs3kkJvTUtMaciqlj5d4I4uHaY9OqRNYfP+BxRvsRP1g/ DAJH4is56rQYvN706CoZFfmCVwYG+Qwk3iNskONA48hxTuJFpYoV8rTAtazL0y/WpClh Qc6rywAU+sW/aRXflPVFB6tMEevtvxpXqnkcB70pDoXUABUpZpZ8w0pYjV6OSg5MrzKE j8zbRWDLbbuaom0yYTbbYy+Bw+kxDS05+T/WLK3Mtehgx6VM6ta2ZBEJ8aHAgVKmSIqQ grhGxGde+mjdNVFtUGFXZSpualG7QdCqDP0BFMkKFmSbwPRFSzhTMDXt72wvbhdaZ0LL HLiw== X-Gm-Message-State: AGRZ1gIrj5qiI4YOmt02N7X22+ToK8FfQKnQPrQxMIX1ROXg+2H6f8in T1q5WL8wpAgYnGON00yrhJJL0NUE X-Google-Smtp-Source: AJdET5cErGwNmqKIla/qydmYOXeb/6v8CglW/G9/Hj54lfYHn5Fd5MQrqBbMhVidc30n+9sVv7dCng== X-Received: by 2002:a0d:e706:: with SMTP id q6-v6mr7978919ywe.436.1541097009458; Thu, 01 Nov 2018 11:30:09 -0700 (PDT) Return-Path: Received: from [192.168.10.219] (mobile-166-170-53-207.mycingular.net. [166.170.53.207]) by smtp.googlemail.com with ESMTPSA id r13-v6sm6319230ywc.52.2018.11.01.11.30.07 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 01 Nov 2018 11:30:08 -0700 (PDT) Subject: Re: [FlyRotary] Re: Flexplate location / failure To: Rotary motors in aircraft References: Message-ID: <46a16f45-bac9-ef87-acbf-4c0400b76bb6@gmail.com> Date: Thu, 1 Nov 2018 13:32:18 -0500 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: Content-Type: multipart/alternative; boundary="------------F348A32F0E4A01A73E2D67E9" Content-Language: en-US X-Antivirus: Avast (VPS 181101-6, 11/01/2018), Outbound message X-Antivirus-Status: Clean This is a multi-part message in MIME format. --------------F348A32F0E4A01A73E2D67E9 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit On 11/1/2018 12:58 PM, lehanover lehanover@aol.com wrote: > > > In a message dated 10/28/2018 5:49:12 PM Eastern Standard Time, > flyrotary@lancaironline.net writes: > > As a heads-up to new arrivals, the flexplate cracking issue likely > predates use of the engine in aircraft. I've got one that's never > flown that has two cracks. I think Len Hanover mentioned that > mishandling at wrecking yards may be one cause (dropping the > engine on the flexplate when storing it). It doesn't seem to be > limited to rotaries, either. > https://www.google.com/search?ei=kizWW_L1KYOuzwKdkaLYBA&q=+flexplate+crack+symptoms&oq=+flexplate+crack+symptoms&gs_l=psy-ab.3..0.9099.9099..10752...0.0..0.153.153.0j1......0....1..gws-wiz.ntPTjk3KElA > > Bottom line for me is to check before using. That's how I > discovered cracks in mine. > > Charlie > > On Sun, Oct 28, 2018 at 12:48 PM David Leonard wdleonard@gmail.com > > wrote: > > Hi Joe, > Yes, my flex plate not only developed cracks but basically > disintegrated.  Keep in mind that I was running about 300hp at > rookie school for Reno.  None the less, the flex plate was > never designed to transmit the output of engine, just allow > the starter to turn it over.  The lightening holes in it alow > flexing that initiated the cracks, then the whole thing > shattered. Surprisingly, in my case the pieces happend to jam > together in such a way that it still functioned until I > happend to find it on inspection several flight hours later. > > All the details of my fix are in the archives somewhere, but > basically I replaced the flex plate with an off the shelf > lightweight flywheel that I addapted to accept tracys damper > plate.  I took it to a machine shop to have the mounting holes > correctly placed.  I also had it balanced, but I probably > could have skipped that step.  I also had to machine a recess > into Tracys mounting plate to allow the starter to reach the > teeth on the flywheel.  Details are in the archivees > somewhere.  That was going on in June July and Aug of 2011, > which may make it easier to find. > > Tracy also engineered a fix.  His solution is in the archives > too.  He also seemed to think that the flex plate was good > enough for a normially aspirated 13b, but after seeeing what > happend to mine, I believe that even a n.a. 13b would > eventually fatugue the flex plate into the same result.   As I > recall, at least one other person detected cracks in the same > place. > > Best, > Dave Leonard > > On Sun, Oct 28, 2018, 4:23 AM Joseph Berki > jskmberki@windstream.net > > wrote: > > I believe that Dave Lenard had an issue with cracks > appearing in the flexplate.  He came up with a solution > and does anyone recall  the details of the solution and > would it work for all 13bs with Tracy’s PSRU? > > Joe Berki > > On the racer, I built a small steel flywheel just big > enough to fit up a 5 1/4" Tilton dual disc clutch pack. > The front side needed to have about 1/4" spigot so as to > clear the flex plate which has a slight conical shape.  I > just bolted the flywheel on over the flex plate. Never a > problem on the  95 RX-7. a big problem on a sports racer I > built. The driver defeated the rev limiter by shifting > into 1st rather than 3rd while already turning about 9,500 > RPM. The transmission was a Hewland FT-200, dog ring > style, so it went right into the selected gear.  The flex > plate has only 6 welds to keep the ring gear on the flex > plate. The ring gear broke next to one weld. The free end > tried to machine the bell housing into 2 pieces. The ring > gear also rolled outboard about 30 degrees. It wanted out > and almost made it. > > On the replacement ring gear I TIG welded an additional 6 > welds and added 12 welds to the back of the ring gear. > > Since you do not need a wear surface for the airplane > installation, just a piece of aluminum plate could be used > to produce a similar flywheel. The flex plate is just used > to start the engine and delivers no torque loads to the > gear box. > > Lynn E. Hanover > Len, if Tracy's damper plate is used, it bolts to the flex plate, just inside of the ring gear. So for our purposes, the flex plate does deliver torque loads to the gear box. Charlie (apologies for the random order of posts) --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus --------------F348A32F0E4A01A73E2D67E9 Content-Type: text/html; charset=utf-8 Content-Transfer-Encoding: 8bit
On 11/1/2018 12:58 PM, lehanover lehanover@aol.com wrote:


In a message dated 10/28/2018 5:49:12 PM Eastern Standard Time, flyrotary@lancaironline.net writes:

As a heads-up to new arrivals, the flexplate cracking issue likely predates use of the engine in aircraft. I've got one that's never flown that has two cracks. I think Len Hanover mentioned that mishandling at wrecking yards may be one cause (dropping the engine on the flexplate when storing it). It doesn't seem to be limited to rotaries, either.
https://www.google.com/search?ei=kizWW_L1KYOuzwKdkaLYBA&q=+flexplate+crack+symptoms&oq=+flexplate+crack+symptoms&gs_l=psy-ab.3..0.9099.9099..10752...0.0..0.153.153.0j1......0....1..gws-wiz.ntPTjk3KElA

Bottom line for me is to check before using. That's how I discovered cracks in mine.

Charlie

On Sun, Oct 28, 2018 at 12:48 PM David Leonard wdleonard@gmail.com <flyrotary@lancaironline.net> wrote:
Hi Joe,
Yes, my flex plate not only developed cracks but basically disintegrated.  Keep in mind that I was running about 300hp at rookie school for Reno.  None the less, the flex plate was never designed to transmit the output of engine, just allow the starter to turn it over.  The lightening holes in it alow flexing that initiated the cracks, then the whole thing shattered.  Surprisingly, in my case the pieces happend to jam together in such a way that it still functioned until I happend to find it on inspection several flight hours later.

All the details of my fix are in the archives somewhere, but basically I replaced the flex plate with an off the shelf lightweight flywheel that I addapted to accept tracys damper plate.  I took it to a machine shop to have the mounting holes correctly placed.  I also had it balanced, but I probably could have skipped that step.  I also had to machine a recess into Tracys mounting plate to allow the starter to reach the teeth on the flywheel.  Details are in the archivees somewhere.  That was going on in June July and Aug of 2011, which may make it easier to find.

Tracy also engineered a fix.  His solution is in the archives too.  He also seemed to think that the flex plate was good enough for a normially aspirated 13b, but after seeeing what happend to mine, I believe that even a n.a. 13b would eventually fatugue the flex plate into the same result.   As I recall, at least one other person detected cracks in the same place.

Best,
Dave Leonard

On Sun, Oct 28, 2018, 4:23 AM Joseph Berki jskmberki@windstream.net <flyrotary@lancaironline.net> wrote:

 

I believe that Dave Lenard had an issue with cracks appearing in the flexplate.  He came up with a solution and does anyone recall  the details of the solution and would it work for all 13bs with Tracy’s PSRU?

Joe Berki

 

On the racer, I built a small steel flywheel just big enough to fit up a 5 1/4" Tilton dual disc clutch pack. The front side needed to have about 1/4" spigot so as to clear the flex plate which has a slight conical shape.  I just bolted the flywheel on over the flex plate. Never a problem on the  95 RX-7. a big problem on a sports racer I built. The driver defeated the rev limiter by shifting into 1st rather than 3rd while already turning about 9,500 RPM. The transmission was a Hewland FT-200, dog ring style, so it went right into the selected gear.  The flex plate has only 6 welds to keep the ring gear on the flex plate. The ring gear broke next to one weld. The free end tried to machine the bell housing into 2 pieces. The ring gear also rolled outboard about 30 degrees. It wanted out and almost made it.

On the replacement ring gear I TIG welded an additional 6 welds and added 12 welds to the back of the ring gear. 

Since you do not need a wear surface for the airplane installation, just a piece of aluminum plate could be used to produce a similar flywheel. The flex plate is just used to start the engine and delivers no torque loads to the gear box. 

Lynn E. Hanover

Len, if Tracy's damper plate is used, it bolts to the flex plate, just inside of the ring gear. So for our purposes, the flex plate does deliver torque loads to the gear box.

Charlie
(apologies for the random order of posts)

Virus-free. www.avast.com
--------------F348A32F0E4A01A73E2D67E9--