X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from mail-qy0-f202.google.com ([209.85.221.202] verified) by logan.com (CommuniGate Pro SMTP 5.2.16) with ESMTP id 3842005 for flyrotary@lancaironline.net; Tue, 08 Sep 2009 21:42:17 -0400 Received-SPF: pass receiver=logan.com; client-ip=209.85.221.202; envelope-from=rwstracy@gmail.com Received: by qyk40 with SMTP id 40so589589qyk.8 for ; Tue, 08 Sep 2009 18:41:42 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:sender:received:in-reply-to :references:date:x-google-sender-auth:message-id:subject:from:to :content-type; bh=Bj4WOZQcByFvQOK8dFb9+vEEotyw9Y0mJMdTetTkVBM=; b=Oa/sNk48wdgA1kIK98fCi3jPi+g3yW25uLj5owrgSFvfr1vT+HXYgXjtSnkQFkWh+c fpnsemo+tApt9fBMRUwByqnq6yuW2GKyNfr61celE96yR0RUqFx+3BeQmjM33XQbth7j V+fUef7dXdZ5YJpdsK3YNMmysprv3Ws06pXgA= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:sender:in-reply-to:references:date :x-google-sender-auth:message-id:subject:from:to:content-type; b=eEHNGCBilphg676tTujKp9NesbTMPH4ToTRqy/Ubwcx7tI0l73MHcYXrKW6GEkl6IY row/2J/C+4UAwidl5TrQHxzIt2U1QgyHvuTFlsg6dkkTtqP6TIDR1dmvASctedNxA7y6 BI0jX4U0J0jvMwbuhY+sRaaWFeX3PDJTg7hUw= MIME-Version: 1.0 Sender: rwstracy@gmail.com Received: by 10.224.96.88 with SMTP id g24mr10612332qan.361.1252460502213; Tue, 08 Sep 2009 18:41:42 -0700 (PDT) In-Reply-To: References: Date: Tue, 8 Sep 2009 21:41:42 -0400 X-Google-Sender-Auth: abd2b791e9e93c83 Message-ID: <1b4b137c0909081841r537e5442r8a74287735ee7f89@mail.gmail.com> Subject: Re: [FlyRotary] Re: At long last, Second Flight From: Tracy Crook To: Rotary motors in aircraft Content-Type: multipart/alternative; boundary=00c09f89965f54668a04731b2f14 --00c09f89965f54668a04731b2f14 Content-Type: text/plain; charset=ISO-8859-1 Thanks for the reports on this guys. Yes, very well described on the Static & Dynamic friction Steve. I know exactly what you mean from the many times I've pulled the 13B through both hot & cold. The reason I brought it up on the 20B is the more closely spaced compression events on it (like Mark pointed out) make it harder to feel what is going on as well as the 50% higher friction you would expect from more parts in contact. When the friction goes up when hot, it is harder to sense the compression cycles at all so it feels very different than the 13B with more 'space' between compression cycles. But after discussing it and thinking about it I'm fairly certain it is normal. Another clue is that if it were abnormal friction it would have either seized up or freed up by now. Tracy On Tue, Sep 8, 2009 at 6:46 PM, sboese wrote: > Congratulations Tracy on the two safe flights so far. I think we all have > a > vested interested in your keeping the flights this way. > > My 13B is harder to start turning and keep turning with the prop when it is > warm compared to cold. This is felt when compression isn't adding to the > load. The additional load due to compression seems more with the cold > engine compared to when it is hot. In other words, the coefficients of > static and dynamic friction increase when my engine is hot while the > compression load seems to decrease. My experience is limited to just my > one > engine. > > Steve Boese > > > > -- > Homepage: http://www.flyrotary.com/ > Archive and UnSub: > http://mail.lancaironline.net:81/lists/flyrotary/List.html > --00c09f89965f54668a04731b2f14 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Thanks for the reports on this guys.
=A0 Yes,=A0 very well described on = the Static & Dynamic friction Steve.=A0 I know exactly what you mean fr= om the many times I've pulled the 13B through both hot & cold.=A0= =A0 The reason I brought it up on the 20B is the more closely spaced compre= ssion events on it (like Mark pointed out) make it harder to feel what is g= oing on as well as the 50% higher friction you would expect from more parts= in contact. =A0 When the friction goes up when hot, it is harder to sense = the compression cycles at all so it feels very different than the 13B with = more 'space' between compression cycles. =A0 But after discussing i= t and thinking about it I'm fairly certain it is normal.=A0 Another clu= e is that if it were abnormal friction it would have either seized up or fr= eed up by now.

Tracy=A0

On Tue, Sep 8, 2009 at 6:46= PM, sboese <sboese= @uwyo.edu> wrote:
Congratulations Tracy on the two safe flights so far. =A0I think we all hav= e a
vested interested in your keeping the flights this way.

My 13B is harder to start turning and keep turning with the prop when it is=
warm compared to cold. =A0This is felt when compression isn't adding to= the
load. =A0The additional load due to compression seems more with the cold engine compared to when it is hot. =A0In other words, the coefficients of static and dynamic friction increase when my engine is hot while the
compression load seems to decrease. =A0My experience is limited to just my = one
engine.

Steve Boese

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