Elite Elavator Horn Problem

[Alan Hepburn]

Roger:

Further to my last on this, you asked how to ensure that the horns (or
spades) don't come out twisted relative to the elevator. I said mine
were pretty well spot on, but couldn't remember how I'd done this. It
seemed that plain good luck couldn't have been it, particularly when
building anything with "Murphy" in the name! Well, now I remember, and
you're going to kick yourself, it's so darned simple. You draw a line
on a piece of nice rigid, straight material long enough to reach from
the tip of the spade to the elevator tailing edge. Then you drill 4 #
11 holes along this line, spaced to line up with the tooling holes on
the elevator and spade ribs. You then cleco or bolt this material to in
place, and remove it when the spade is finished. I used some aluminum
channel I had around, but I guess plywood and AN3 bolts would also do
fine.

I can't help thinking they did the same when they built the prototype,
and they just left out this little tip to challenge the student. You'll
find this is typical as you move through the thing. Never take the
instructions as being full and complete.

For example, you're going to encounter much the same thing on the rudder
spade, which it turns out I built first. I'd figured out the above
trick, but for lateral positioning I simply relied on the material being
straight, and confirmed with a square that the spade was at right angles
to the leading edge. Close, but I'd have been better to take a more
thorough look at that website with all the Elite photos, where they
recommend temporarily installing the rudder on the fin to set up the
alignment. Then you can set up a spare at root and tip of the spade to
get it dead parallel with the top of the fin. Mine diverges about 1/16"
of an inch (fortunately, it would have been pretty tight if it had been
the other way). I'll always notice this, though probably nobody else
will. Another real basic one - save the cutoff stringers from the stab,
and use them on the fin. The guy I bought my kit from had chucked them
out, and I wound up having to buy extra stringers.

Howvere, as I say, you may want to consider a design change here, and
Sean's idea sounds like it may work. Well see yow the initial flights
go. I just don't know enough about areodynamics to say whether a 10%
reduuction in elevator area will be critical. I suppose it depends how
much elevator authority the thing has to begin with. Anybody out there
with Elite experience, do you tend to run out of elevator in the round
out at forward CoG locations? Alternatives, such as shortening the
spades chord-wise would be much more complicated.

I do happen to have a couple of spare EL-402s which must have been in
the kit, if that's any use, but I think you can probably use the
originals and just replace the spade skins. Just drill a key #30 hole
to take the tip cleco, then offset all the other holes from their
original position by 5/16". Not quite a regular drill pattern, but good
enough for all but the perfectionists.

Regards, Al.



*-------------------------------------------------------------------------*
To unsubscribe from this list go to:
http://www.dcsol.com:81/public/code/html-subscribe.wcx
Archives located at http://rebel:builder@www.dcsol.com:81/default.htm
To contact the list admin, e-mail mike.davis@dcsol.com
*-------------------------------------------------------------------------*








-----------------------------------------------------------------
List archives located at: https://mail.dcsol.com/login
username "rebel" password "builder"
Unsubscribe: rebel-builders-unsubscribe@dcsol.com
List administrator: mike.davis@dcsol.com
-----------------------------------------------------------------

[Roger Cole]

Alan,

Thanks. That is a great idea. I only have to do one horn; the other is
spot on.

The next problem is how to get the rows of #40 holes in tip skin properly
aligned with the two rows of #30 holes in the top elevator skin and the two
rows of #30 holes in the bottom elevator skin. If I can get two holes
correctly aligned in the top and two holes correctly aligned in the bottom,
I can cleco the old skin to the new one as a template. The problem is how
to align the first two holes in top and bottom. Any ideas?
--
Roger Cole <rcole927@earthlink.net>
Elite 709

----------

From: "Alan Hepburn" <ahepburn@renc.igs.net>
To: murphy-rebel@dcsol.com
Subject: Re: Elite Elavator Horn Problem
Date: Sun, Jun 8, 2003, 5:06 AM

Roger:

Further to my last on this, you asked how to ensure that the horns (or
spades) don't come out twisted relative to the elevator. I said mine
were pretty well spot on, but couldn't remember how I'd done this. It
seemed that plain good luck couldn't have been it, particularly when
building anything with "Murphy" in the name! Well, now I remember, and
you're going to kick yourself, it's so darned simple. You draw a line
on a piece of nice rigid, straight material long enough to reach from
the tip of the spade to the elevator tailing edge. Then you drill 4 #
11 holes along this line, spaced to line up with the tooling holes on
the elevator and spade ribs. You then cleco or bolt this material to in
place, and remove it when the spade is finished. I used some aluminum
channel I had around, but I guess plywood and AN3 bolts would also do
fine.

I can't help thinking they did the same when they built the prototype,
and they just left out this little tip to challenge the student. You'll
find this is typical as you move through the thing. Never take the
instructions as being full and complete.

For example, you're going to encounter much the same thing on the rudder
spade, which it turns out I built first. I'd figured out the above
trick, but for lateral positioning I simply relied on the material being
straight, and confirmed with a square that the spade was at right angles
to the leading edge. Close, but I'd have been better to take a more
thorough look at that website with all the Elite photos, where they
recommend temporarily installing the rudder on the fin to set up the
alignment. Then you can set up a spare at root and tip of the spade to
get it dead parallel with the top of the fin. Mine diverges about 1/16"
of an inch (fortunately, it would have been pretty tight if it had been
the other way). I'll always notice this, though probably nobody else
will. Another real basic one - save the cutoff stringers from the stab,
and use them on the fin. The guy I bought my kit from had chucked them
out, and I wound up having to buy extra stringers.

Howvere, as I say, you may want to consider a design change here, and
Sean's idea sounds like it may work. Well see yow the initial flights
go. I just don't know enough about areodynamics to say whether a 10%
reduuction in elevator area will be critical. I suppose it depends how
much elevator authority the thing has to begin with. Anybody out there
with Elite experience, do you tend to run out of elevator in the round
out at forward CoG locations? Alternatives, such as shortening the
spades chord-wise would be much more complicated.

I do happen to have a couple of spare EL-402s which must have been in
the kit, if that's any use, but I think you can probably use the
originals and just replace the spade skins. Just drill a key #30 hole
to take the tip cleco, then offset all the other holes from their
original position by 5/16". Not quite a regular drill pattern, but good
enough for all but the perfectionists.

Regards, Al.



*-------------------------------------------------------------------------*
To unsubscribe from this list go to:
http://www.dcsol.com:81/public/code/html-subscribe.wcx
Archives located at http://rebel:builder@www.dcsol.com:81/default.htm
To contact the list admin, e-mail mike.davis@dcsol.com
*-------------------------------------------------------------------------*

*-------------------------------------------------------------------------*
To unsubscribe from this list go to:
http://www.dcsol.com:81/public/code/html-subscribe.wcx
Archives located at http://rebel:builder@www.dcsol.com:81/default.htm
To contact the list admin, e-mail mike.davis@dcsol.com
*-------------------------------------------------------------------------*








-----------------------------------------------------------------
List archives located at: https://mail.dcsol.com/login
username "rebel" password "builder"
Unsubscribe: rebel-builders-unsubscribe@dcsol.com
List administrator: mike.davis@dcsol.com
-----------------------------------------------------------------