Right Elevator Trailing Edge

smittysrv · Post by **smittysrv** » Thu Dec 29, 2005 10:13 am

OK, I'm bummed. I finished riveting the trailing edge on the right elevator and I noticed that there is a slight 1/16" dip along what have should have been a straight line. The instructions anything greater than a 0.1 of and inch bend is unacceptable, so an 1/16 inch dip is OK, but it still ticks me off. Anyone else have this problem?

I think this must have happened when I drilled the holes into the aluminum angle and the middle of the bottom skin pooched out farther than the middle of the top skin.

Post by **Spike** » Thu Dec 29, 2005 10:23 am

Do you have any pictures of it Smitty? Off the top of my head I would say don't worry about it. Youll forget about it soon enough.

-- Spike

captain_john · Post by **captain_john** » Thu Dec 29, 2005 11:55 am

Yah Smitty...

Let's see what you are talking about!

CJ

smittysrv · Post by **smittysrv** » Thu Dec 29, 2005 12:17 pm

Sorry Guys. I tried, but it's damn near impossible to get a shot "down the line" that's in focus. I was just curious if anyone else had run into this. I think I ain't gonna' worry about.

Thanks!

captain_john · Post by **captain_john** » Thu Dec 29, 2005 1:19 pm

Smitty, we aren't gonna let you off the hook that easily!

I *think* I know what you are saying. The trailing edge is deflected more to either the top or bottom. Kind of a curl to it? Like Bill's in this thread:

http://www.rivetbangers.com/cgi-php/for ... iling+edge

Would what Jim did in this thread:

http://www.rivetbangers.com/cgi-php/for ... iling+edge

...help you out?

CJ

smittysrv · Post by **smittysrv** » Thu Dec 29, 2005 2:09 pm

Hi CJ.

Thanks for the email back. The trailing elevator edge on the 9A is like the trailing on the rudder. You have to pull the top skin and bottom skin together with a WEX wedge glued between. The difference is that the top skin has pre-drilled holes and the bottom skin doesn't, never does the WEX wedge. So you have to drill through the pre-drilled hole in the top skin, through the wedge, through the bottom skin and then into an aluminum angle (that keeps the whole thing straight. My problem was that I coudn't see what the bottom skin was doing because the wedge is in the way. While I was drilling the middle of the elevator, the bottom skin pooched aft without me realizing. Then when I riveted everything, the bottom skin forced the bend in the trailing edge.

I'm well within Van's accepted range of warp, so I'm just going to live with it. Besides, my wife told me if I didn't shut up about it, she was going to kick my ass.

Yous guys have a goodun!

Post by **Spike** » Thu Dec 29, 2005 2:14 pm

smittysrv wrote:Besides, my wife told me if I didn't shut up about it, she was going to kick my ass.

That is why its important to have a woman involved with the build. It helps to smack us back to reality when needed

cjensen · Post by **cjensen** » Thu Dec 29, 2005 4:13 pm

ain't that the truth!

captain_john · Post by **captain_john** » Thu Dec 29, 2005 4:37 pm

My wife takes a laissez-faire approach to aircraft building.

She is just happy that the dog and I are not in the house!

Smitty, glad that you arrived at a conclusion!

CJ

jim_geo · Post by **jim_geo** » Thu Dec 29, 2005 7:00 pm

Ok, I noticed that when riveting the trailing edge of the rudder I could use the rivet gun to slightly alter the edge and make things a little straighter. My edge had a spot that was definitely deflected. By just turning down the pressure on the gun I was able to straighten it out to where I couldn't measure any out of line. Secret here seems to be to turn your pressure way down as in 10 psi or so and just play the gun back and forth in the local area of the offensive deflection. Also, if you were to think of this condition as cupping you would be hammering on the inside of the cup rather than on the outside. I think you're actually trying to push molecules apart when doing this. Another helpful hint may also be that when sighting down something with a small deflection to it my eye seems to locate the area as being closer to me than it really is. I have learned to run a finger down whatever I'm sighting on and mark the location that way. Usually it will be several inches farther from me than I would have actually thought it to be. I'm not saying this is how it oughta be done I'm just saying that this worked for me.

Post by **Spike** » Fri Dec 30, 2005 7:13 am

Jim,

Are you saying that you moved the gun around the area, implying that you werent always on the rivet?

jim_geo · Post by **jim_geo** » Fri Dec 30, 2005 2:48 pm

I'm not implying anything. I'm out right saying it. Remember that there is an AEX in there also and that is what I was trying to get to change shape. I would never beat on just the skin. I'm also talking rudder here which as I understand it is the same construction as the elevators on the 9. Even with the pressure turned way down things move pretty fast.

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