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<DIV>Lance, the rounded leading edge of the control surface was practiced way
back in the golden (stone?) age of model aviation, when the hinge material was
plain thread. Believe it or not, the control surfaces were literaly sewen into
the wing or stab or fin. Surface actuation essentially allowed the surface to
"roll", ie- it did not pivot about a single axis as present set-ups do</DIV>
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<DIV>Yor observation is correct: a rounded edge hinged with present hinges, will
tend to bind.</DIV>
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<DIV>MattK</DIV>
<DIV> </DIV>
<DIV>In a message dated 11/25/2004 12:47:09 AM Eastern Standard Time,
patterndude@comcast.net writes:</DIV>
<BLOCKQUOTE
style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: blue 2px solid"><FONT
style="BACKGROUND-COLOR: transparent" face=Arial color=#000000 size=2>Please
someone explain this rounded control surface thing to me. If we use
<BR>a CA hinge and but the aileron to the wing, then the only way the surface
<BR>can move is if it has a beveled point. A rounded interface will bind
unless <BR>the aileron has a gap to begin with. However, if all we are
saying is to <BR>round the part of the bevel that blends into the aileron,
then I get it.<BR><BR>Confused again....<BR>--Lance<BR><BR>----- Original
Message ----- <BR>From: "John Pavlick" <jpavlick@idseng.com><BR>To:
<discussion@nsrca.org><BR>Sent: Wednesday, November 24, 2004 8:38
PM<BR>Subject: RE: wing tip shape<BR><BR><BR>> Hey, That's how they are on
my Super Kaos Jr. Not exactly 45 degrees, but<BR>> the outboard 3" is
tapers toward the tip. If you do this by sanding the<BR>> bottom edge of
the aileron at the tip, you also add a little washout to <BR>> help<BR>>
prevent tip stalls. Not sure if it's enough to make a difference but I
can<BR>> land this plane nose high without any surprises. Someone mentioned
<BR>> rounding<BR>> the leading edge of control surfaces rather than
beveling them - I've <BR>> always<BR>> done this unless the surface is
really thick (like a barn-door aileron). <BR>> In<BR>> the 1st U.S. R/C
Flight School training manual (the red one) the idea of<BR>> control
surfaces with round leading edges that are slightly thicker than <BR>>
the<BR>> fixed surface is discussed. They claim it reduces flutter (without
sealing<BR>> the gaps) and makes the control response less speed sensitive.
Has anyone<BR>> tried this? It would be interesting to hear if it works on
pattern planes.<BR>><BR>> John Pavlick<BR>>
http://www.idseng.com<BR>><BR>><BR>>> -----Original
Message-----<BR>>> From: discussion-request@nsrca.org<BR>>>
[mailto:discussion-request@nsrca.org]On Behalf Of John Ferrell<BR>>>
Sent: Wednesday, November 24, 2004 5:43 PM<BR>>> To:
discussion@nsrca.org<BR>>> Subject: Re: wing tip
shape<BR>>><BR>>><BR>>> If you carry the aileron all the way
to the tip it is good<BR>>> medicine to clip<BR>>> the trailing
outboard corner at 45 degrees to help suppress any<BR>>> tendency
to<BR>>> flutter. It is common practice on combat
models.<BR>>><BR>>> John Ferrell<BR>>> My Competition is not
my enemy!<BR>>> http://DixieNC.US</FONT></BLOCKQUOTE></DIV>
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