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  #11  
Old 07-30-2019, 02:54 PM
scsmith scsmith is offline
 
Join Date: Jan 2008
Location: Ashland, OR
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It is possible that you are fooling yourself about any twist in the surfaces. One way I tell is to look at the surface from some significant distance behind it, looking at the trailing edge. If you shift your position so that the line of the trailing edge intersects the "horizon line" of the control surface at about at the thickest point, you can tell if the trailing edge is parallel to the horizon line.

Another possibility to suggest, and bear in mind I am not very familiar with the -14 kit assembly, would be if the flap hinges were mounted to the wing a little too far forward. This would have the effect of deflecting the flap downward a little when the flap leading edge rests on the drag spar. It would only take a 1/16" shift in the flap hinge point to move the flap trailing edge down 1/4".
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  #12  
Old 07-30-2019, 03:11 PM
Bavafa Bavafa is offline
 
Join Date: Oct 2007
Location: Sacramento, CA
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Quote:
Originally Posted by Bsquared View Post
I have a 3/16” mismatch on one of my ailerons when checking using the templates in the wing stand. My Aileron trail edge is also “dead straight” but when I lay it on a flat surface.... a granite countertop....I can rock it about the same 3/16” as the mismatch when installed on the wing. My plan is to proceed ahead and see if I need to adjust the wing tip after I fly it for a while.
As far as I know this is the realistic way of finding if there is a twist in a controlling surface. The line of rivets next to the trailing edge of the wing could be near dead on and yet have a twist.

Jon,
You have the correct Jig, one of the first thing I checked in your first picture. The new Jig has a small hole in it to indicate new vs. old.
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  #13  
Old 07-30-2019, 03:56 PM
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mulde35d mulde35d is offline
 
Join Date: Dec 2017
Location: Williamsburg, VA
Posts: 205
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Appreciate the additional insight. I’ll pull the flaps and ailerons and place them on a piece of granite countertop to check again. Last time I used benches, straight boards, and a digital level. Granite countertops are likely better than all 3 of those together.
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RV-14A - N122X (IO-390 TB, WW 74HRT, G3X)
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  #14  
Old 07-31-2019, 03:30 PM
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mulde35d mulde35d is offline
 
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Location: Williamsburg, VA
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Talked with builder assistance tonight (they were worn out from Osh), but they said if the flaps and ailerons have no twist (which they don't as confirmed by the granite countertop) then it is likely the rear spar / attachment points on the wings have a slight bit of twist. Unfortunately this was the final conclusion that I didn't want to hear, but the good news is that it isn't as big a deal as I thought. They recommended rigging with the Jig as I did and checking again after final installation of the wings on the aircraft. After the first flight they said I could play with the rigging to eliminate any roll and get them as close to even with the flaps as possible.

Unfortunately no smoking guns on this one, will have to wait a year until first flight to get to the final solution. Thanks to everyone who provided additional areas to check.
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RV-14A - N122X (IO-390 TB, WW 74HRT, G3X)
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  #15  
Old 07-31-2019, 05:10 PM
Avoca1us Avoca1us is offline
 
Join Date: Jun 2015
Location: Reynoldsburg, OH
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I had the same issue with my plane. I used the aileron jig for alignment and then rigged the flaps with the ailerons. I've been flying for 3 months with no heavy wing or rudder trim needed. Slow build fuse, quick build wings.

Mike
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