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  #1  
Old 10-03-2010, 10:24 PM
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newimaging newimaging is offline
 
Join Date: May 2010
Location: Los Angeles, CA
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Default Right Elevator counter weight trimming

I just did my trimming on the E-714 lead counterbalance part for the right side elevator. It says that the material being trimmed is for balancing, and to account for paint later.
Does that mean once you have the left elevator done you shave off some more lead to balance it as far as weight is concerned ? It's not a material trim for any clearance I don`t think.
I am sure this question will resolve 50 pages later, but just curious.

Christian
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  #2  
Old 10-03-2010, 10:28 PM
terrye terrye is offline
 
Join Date: Feb 2010
Location: Vancouver, BC, Canada
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Default Mass balance

Yes, the lead mass is intended to be trimmed by drilling small holes so that the elevator is balanced when it is fully finished (painted, tip mounted and painted). It is important to balance these control surfaces to avoid flutter, a divergent oscillation of the surface.
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  #3  
Old 10-03-2010, 10:57 PM
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L.Adamson L.Adamson is offline
 
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Location: KSLC
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Default

My elevators are connected together for balancing. I removed quite a bit of lead in the right side. After painting, I had to put most of the lead back, because of the paint weight. Just something to keep in mind. My plane is a 6A.

L.Adamson
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  #4  
Old 10-03-2010, 11:03 PM
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lostpilot28 lostpilot28 is offline
 
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Location: Boise, ID
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I balanced mine seperately. I took a whole lot o' lead out of the right side, and added a little bit to the left. I filled in the hole with expanding foam, then epoxied over it. I did this after painting, too.
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  #5  
Old 10-04-2010, 12:52 AM
thelynns thelynns is offline
 
Join Date: Jan 2008
Location: Vancouver, WA
Posts: 84
Default Adding weight back

I trimmed both sides by mistake. How the heck do add weight back?
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  #6  
Old 10-04-2010, 07:00 AM
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Bullseye Bullseye is offline
 
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Quote:
Originally Posted by thelynns View Post
How the heck do add weight back?
I added these for future weight addition.


http://n999za.files.wordpress.com/20...-034-large.jpg

http://n999za.files.wordpress.com/20...-005-large.jpg

You can use a bolt to put a few heavy washers back onto the counterweight ribs. These will allow me to 100% balance for first flight (bare aluminum), and then add weight back after painting at some future point.

For the record, I believe Van's says that is is okay to be overbalanced for the first few flights.

Make sure you put the nutplate on the outboard side (hidden by the permanently mounted elevator tips). The bolt threads from the inside...make sure the bolt is short enough that if it backs out, it won't jam your elevators.

I copied them from someone, but I can't remember who.
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