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<DIV><FONT face=Arial>Bob</FONT></DIV>
<DIV><FONT face=Arial></FONT> </DIV>
<DIV><FONT face=Arial>I've no direct info regarding soft mounts on the big
gassers. It's my understanding that they were used by some TOC competitors.
I've been told that some engine manufacturers advise that using a soft mount
will void the warranty. Also, that using a soft mount results in broken cranks.
Others claim that the big composite airframes are designed to absorb the vibes
and don't need a soft mount. My guess is that just adding a soft mount in
the radial mounting scheme may not work well - but this is a mounting problem
and not a mount problem. </FONT></DIV>
<DIV><FONT face=Arial></FONT> </DIV>
<DIV><FONT face=Arial>Earl</FONT></DIV>
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<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B>
<A title=bob@toprudder.com href="mailto:bob@toprudder.com">Bob Richards</A>
</DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A
title=nsrca-discussion@lists.nsrca.org
href="mailto:nsrca-discussion@lists.nsrca.org">NSRCA Mailing List</A> </DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> Saturday, September 01, 2007 8:18
AM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> Re: [NSRCA-discussion] Metal
Servo Arms</DIV>
<DIV><BR></DIV>
<DIV>Earl,</DIV>
<DIV> </DIV>
<DIV>You are right about soft mounts. One thing I don't understand is why soft
mounts have not made much progress in the larger 50cc+ size planes. </DIV>
<DIV> </DIV>
<DIV>Bob R.</DIV>
<DIV><BR><BR><B><I>Earl Haury <<A
href="mailto:ejhaury@comcast.net">ejhaury@comcast.net</A>></I></B>
wrote:</DIV>
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<DIV><FONT face=Arial>Bob</FONT></DIV>
<DIV><FONT face=Arial></FONT> </DIV>
<DIV><FONT face=Arial>I agree - in reality servo arm / spline strength is
pretty much of a mute point for pattern. I did the tests after a friend
broke an 8411 shaft on a big gasser, and some heli friends claimed the Al
arms stripped the spines from nylon servo shafts. Takes excessive force to
do either. </FONT></DIV>
<DIV><FONT face=Arial></FONT> </DIV>
<DIV><FONT face=Arial>Recall changing a clevis to a ball link on a Rossi
carb arm - arm broke on the first flight, a doubled arm broke on the next -
back to a clevis and never broke another. Vibratory forces aren't understood
by most - but experience is a great teacher.</FONT></DIV>
<DIV><FONT face=Arial></FONT> </DIV>
<DIV><FONT face=Arial>Somewhere I've some DSA data gathered with
mini-accelerometers mounted on aileron servo mounts, firewalls, etc. One
look at those data with and without a soft mount will make one a believer in
soft mounts!</FONT></DIV>
<DIV><FONT face=Arial></FONT> </DIV>
<DIV><FONT face=Arial>Earl</FONT></DIV>
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