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Rudder Trim

Rallylancer122

Well Known Member
Well, I've come to the inevitable conclusion that I need a trim tab on my rudder. I was really trying to avoid this as I recently built a new rudder for the plane (long story) and it looks great. Trim tabs are ugly, and I don't want to rivet one onto my pretty rudder. I've tried rigging up an adjustable bungee system that pulls on the rudder pedal, and it somewhat works, but not great and must be adjusted as speed/power changes. So, I got to thinking....

Has anybody tried messing with the fiberglass bottom cap? I was thinking of molding a trim tab down there as it will be less conspicuous. I figure I can temporarily rivet an aluminum tab on there until I find the right size, and then mold that shape into the cap. Just curious if this has been tried yet.

Thanks,
Dennis
 
I made this for my -6A (-7 rudder). It works quite well. Currently held on with that heavy duty 3M double-sided tape.
20191220-102335.jpg

20191220-102331.jpg
 
I have a small wedge on my rudder. Works great, and hardly even noticeable. I?ll take a picture next time I?m at the hangar.
 
Right foot...

I'm in the same boat. It's something that I say "I'll do that...later".
I like the idea of modifying the fiberglass cap,
Following for more ideas...:D
 
If you use a small wedge and paint it the same as your rudder its hardly noticable.

Think of Cessna 172's, they have a big ugly one that nobody pays attention to.
 
I installed rudder pedal return springs on my -6 & -7 mainly to keep tension on the rudder cables. My -6 required right rudder in cruise, so I simply installed a slightly stiffer spring on the right rudder pedal. Solved the rudder trim problem without any external tab.
 
Thanks for the advice guys. I've tried springs and they don't work on my plane. If they work for others, great. My plane is polished so a trim tab will stick out. My Dad had a wedge on there at one point and it stuck out as well. Hence I'm looking for a different solution.

DEM
 
I used a wedge on both of my RV8 builds and mounted both at the bottom right above the tail light bubble. After I got the length right after flight testing, I glassed the wedge in, molded right onto the bubble. After painting, unless I tell you it?s there, you wouldn?t notice.
 
I made this for my -6A (-7 rudder). It works quite well. Currently held on with that heavy duty 3M double-sided tape.
20191220-102335.jpg

When I was scrolling down the page I only saw the first picture and thought that was the entire rudder !! I laughed hard thinking it was a photoshop to mess with the OP as to a tab that really sticks out. :D Then I saw the second picture.
 

Wow, to me that would stick out even more than the small tab. I think it's like everything else with our planes. I hadn't given that tab another thought until now that it was brought up so I'm sure a small tab would look fine on a polished plane except the owner would know it and see it like if it were 3' long and sticking out out a foot !
 
Wow, to me that would stick out even more than the small tab. I think it's like everything else with our planes. I hadn't given that tab another thought until now that it was brought up so I'm sure a small tab would look fine on a polished plane except the owner would know it and see it like if it were 3' long and sticking out out a foot !

Once you cut it to size (depending on amount of trim required), paint and glue to trailing edge it practically disappears. Much much better than a 'tab' IMO. If I remember I'll take a picture of my install.
 
Once you cut it to size (depending on amount of trim required), paint and glue to trailing edge it practically disappears. Much much better than a 'tab' IMO. If I remember I'll take a picture of my install.

I'm sure it looks good painted, I'm just saying the OP's plane is polished plus he already went that route and didn't like it :

...My plane is polished so a trim tab will stick out. My Dad had a wedge on there at one point and it stuck out as well. Hence I'm looking for a different solution.
DEM
 
Wedge on mine for now..

I have a wedge on my -4, as much as I didn't want one, but its pretty common.
If I ever build/rebuild my rudder, I will put a MAC driven trim tab built in (like elevator tab) just like I did on my aileron trim. Pat Hatch did this years ago on his -6 build, and I wish i would have followed then ...I mean, a P-51 has one, and so should an RV!! No more right pedal hold climbing to 10K or left pedal hold on a screaming descent either.
 
If I ever build/rebuild my rudder, I will put a MAC driven trim tab built in (like elevator tab) just like I did on my aileron trim.

We dropped the original rudder while doing the stab spar SB, and put a kink in the trailing edge. This led me to reskin it. Only afterwards, when I realized I needed trim, did I look at our original rudder skin and think of this. It would have been a no brainer to cut out the kink and replace it with a moveable tab. Doh!

And yeah, I could do it now....but I don't want to cut into my shiny new rudder!

And yeah, I realize all this is me being way to anal about the looks of a 20 year old plane that quite frankly is no longer an award winner. But if Dad flew that thing 2000 hours without a tab he must have really not wanted one, so I guess I don't want to be the one who puts it on.

DEM
 
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I used a wedge on both of my RV8 builds and mounted both at the bottom right above the tail light bubble. After I got the length right after flight testing, I glassed the wedge in, molded right onto the bubble. After painting, unless I tell you it?s there, you wouldn?t notice.

Hi Scott,

This sounds like what I was thinking of doing. Is your wedge on the skin, or on the fiberglass cap? Don't suppose you have any pics?

Thanks,
Dennis
 
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