Take a rod end out and cut 1/4" or so off the end of the steering link. Re-thread the hole if the threads are not deep enough to get proper TW alignment. The steering rod link gives more positive steering. An option is to go back to the chain/cable and spring steering which I find more forgiving. The inner hole will give more TW travel for the same rudder input making it more reactive.

Check out Dan Hortons TW alignment post for how the main gear should be aligned for improved handling.
 
I had to shorten the tailwheel link very slightly as mentioned above. Mine had plenty of thread depth remaining so I just chased the threads and reassembled. Torque the lock nuts, a little dab of Torque Seal and you are back all set.
 
Skysailor said:
I had to shorten the tailwheel link very slightly as mentioned above. Mine had plenty of thread depth remaining so I just chased the threads and reassembled. Torque the lock nuts, a little dab of Torque Seal and you are back all set.
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I had to do the same
 
While ya'll are back there, check your tailwheel release point. I'm seeing quite a few which release into full swivel before the rudder reaches its stop. With full rudder applied for a crosswind or swerve recovery, a brake tap is then the only thing remaining between you and a ride into puckerland.

Easy to check. Put the tail up on a stand placed under the stinger where it enters the fuselage, so the rudder and wheel are free to swivel.

Now move the rudder all the way to the stop while holding opposite pressure against the tailwheel. The tailwheel should not release:

Tailwheel Ratio.jpg

With the rudder still against the stop, push the tailwheel the other way. You should feel a slight to moderate resistance, followed by a "pop" and a release into swivel:

Tailwheel Release.jpg

The "pop" is the tombstone pin riding up and out of the ramp in the fork spindle, just as it should when you apply full rudder and tap a brake to spin into your parking spot.

Correcting a premature release generally requires either (1) adding length to the arm on the tailwheel, or (2) moving the cable or link attach point inboard on the rudder arm.
 
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Dan, Would you recommend making new rudder stops instead of changing the chains/linkage?
 
Webb said:
Dan, Would you recommend making new rudder stops instead of changing the chains/linkage?
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I wouldn't. Assuming the stops were set up as directed in the plans, and are symmetrical, the rudder isn't the problem. Don't fix one problem by introducing another.
 
Webb said:
Dan, Would you recommend making new rudder stops instead of changing the chains/linkage?
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Only if the stops are asymmetrical. I've seen that too.

The post 5 issue is a ratio problem, corrected by changing the effective length of one or both arms. You would not change the chains or link.
 
Your timing of the post couldn't be better. Thank you. I just finished hanging the rudder and getting ready to work on the cables (no chains).

If you were doing the initial install, how would you go about finding the optimal length?
 
Empirical experiment. With dual chains or cables, moving the attach point on the rudder horn inboard usually does the trick. May not be able to do that with a single link.
 
A762654D-508F-4123-985C-FF7E5AE14A65_1_105_c.jpeg

One thing to check: The tail spring is held into the fuselage by a single AN3 bolt (I think AN3).

The hole in the fuselage tube may tend to enlarge and allow the tail wheel to lean left or right. Picture attached of enlarged hole.
If that is the case you may be able to ream the tube and the tail spring to AN4. Or as I did, ream the hole and tail spring for a taper pin.
 
I would check the vertical alignment of the tailwheel post. Yours appears to be angled quite a bit aft. Had this problem over time on my -7, eventually I needed to put a slight bend in t/w spring.
 
SMRacer said:
View attachment 66441

One thing to check: The tail spring is held into the fuselage by a single AN3 bolt (I think AN3).

The hole in the fuselage tube may tend to enlarge and allow the tail wheel to lean left or right. Picture attached of enlarged hole.
If that is the case you may be able to ream the tube and the tail spring to AN4. Or as I did, ream the hole and tail spring for a taper pin.
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I did the same thing on my RV6 - taper pin - there’s a few posts about what’s needed to do that. The bolt that’s in there should be an AN4. Enlarging it to AN5 might work, but I would recommend going the taper pin route if that’s your problem. The hole in the fuselage weldment gets hogged out if the initial fit isn’t tight. Mine apparently wasn’t. The weldment metal (4130 steel I assume) is relatively soft compared to the stinger metal. The 386-2 taper pin, as recommended, has a minor diameter (upper end on mine since I tapered from the bottom up) of .255. This taper pin uses a 10-32 threaded end on the minor end. The upper end of the hole in my weldment was hogged out more than this so I had to upsize to a 386-3 taper pin, which has a 1/4-28 threaded end on the minor diameter. This works because the taper is the same on both pins - 1/2” per foot - and fortunately my reamer was long enough to enlarge the hole slightly so I didn’t have to buy another expensive taper pin reamer. Also mentioned is the torque applied to the taper pin nut. It should probably be no more than 1/2 the standard AN 10-32, or AN 1/4-28 nut torque. Removing it, if ever needed can be very difficult.
 
I ended up adding a .75 inch extension to get proper release. I could use another 1/8 inch the release is right at full deflection.

1000004184.jpg
 
Little Wing said:
I ended up adding a .75 inch extension to get proper release. I could use another 1/8 inch the release is right at full deflection.

View attachment 67221
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Hi Rod, do you feel much difference in the handling after this change? As an aside, during my flight testing, I stuck an action camera back there pointed onto the tailwheel to see what it's doing. I was quite surprised at what I saw, and I inferred that the stresses back there are pretty substantial, particularly on rougher surfaces.
 
Just installed and I've only got 3 landings with the extension but it's much less "nervous" on landing, it always felt a bit sensitive stock. I'll probably make another at some point a bit longer to increase the caster force a bit more. Yes my mains are shimmed for proper toe!
 
Little Wing said:
Just installed and I've only got 3 landings with the extension but it's much less "nervous" on landing,
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It should...less angular displacement of the tailwheel for any given rudder pedal input.

Little Wing said:
Yes my mains are shimmed for proper toe!
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Dead parallel, tail down, was a big improvement:

Wheel Alignment

Recently did a field repair involving ad hoc wheel alignment using whatever was handy. It led me to think about my own alignment, as it hadn't been checked since the fuselage was upside down in the shop. Here's the simple, reliable, repeatable, hardware to do it. The bits are cut from scrap...
www.vansairforce.net www.vansairforce.net
 
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