Rudder rigging and pedals

A question for those that have completed their airplanes regarding rigging of the rudder. I pulled the cables tight and drilled the linkages as the plans recommend and then installed everything. The rudder gets to the stop in both directions without difficulty. However, with just a bit more pressure on the pedals, I can make the nuts on the back of the pedal that is being pushed make contact with the firewall. Did anyone else encounter this? I stretched the cables pretty tight before marking and drilling the linkages.

cables tight enough....?

You may want to see if you can track down someone with a cable tensiometer. I thought we had the cables tight until...we borrowed a tensiometer from our local chapter. You'd really be surprised at the difference.
Meade
1/2 RV612RV

the rudder cables are not tensioned

Thanks but the rudder cables are not tensioned, as they are independently linked. Only the stabilator cables are tensioned to a specific value.

JTE (Strange name.....hi),

Yes....the tensiometer is not used for the rudder cables. I have not noticed the problem you describe. All I can suggest is to ensure the wooden box that you built to tension the rudder cables is correct and pull hard on each cable when measuring the links. I used a set of visegrips to pull rather hard on the link at the rudder before I marked it for the holes. Had a friend help me with this step. Would have been harder to do it by myself.

Marty's advice is what I would recommend, double check "the box" dimmesions and & rigging. I think mine are close to touching, and I have not had them bottom out in 50 hours. There have been several time when I have been on ice and had the peddles fully deflected also, and have not bottomed out. Better double check.

cable slack

I have same problem--they just touch as the rudder reaches stops. The cables are pretty slack when I look at them going back through the tail cone section--is this typical??

gary

You will always see slack cable, until you put a bit of pressure on both pedals. As an aside, this is why a rudder lock is important if you park outside in windy conditions.

KRAUSEGB said:

I have same problem--they just touch as the rudder reaches stops. The cables are pretty slack when I look at them going back through the tail cone section--is this typical??

gary

Click to expand...

Yes, they are slack unless you have your feet on the peddles. All of the RV's are like that.

Not necessary to clamp links

It is not necessary to clamp the rudder linkages to the rudder control horn. I centered the rudder, then pulled the links tightly with vise-grips one at a time with one hand and marked the hole with the other hand. I checked to be sure the rudder did not move during the process. After drilling the holes in the linkages, I measured the distance between holes. The long-link holes were exactly 2" apart on center and the short-link holes were exactly 1" apart on center. I do not know if those dimensions were coincidentally whole numbers or Van's designed it that way. After installing all of the hardware, I put the wooden fixture back in. It was a tight fit requiring some gentle persuasion. Then I checked the rudder by measuring distance between the control horn bolt and the aft bulkhead on each side. The two sides are within 1mm of each other. Then I pushed the rudder pedals by hand and they both come within 1/4" of the firewall. I think that I could probably push them against the firewall if I used my foot instead of my hand. If it turns out that the rudder pedals are not even while flying, I can always replace the links. At least I know the distance between the holes. I could increase the distance on one set and decrease the distance on the other set by the same amount.
That wooden fixture will make a good rudder control lock, but I would not want to carry it in the plane.
Joe

Mich48041 said:

That wooden fixture will make a good rudder control lock, but I would not want to carry it in the plane.
Joe

Click to expand...

One of my friends, Al Checca, built this rudder lock for his RV6 and I think it could be adapted to the RV-12. He built it after his RV-6 was caught outside on the ground in a wind storm. Because a lock was not installed, the rudder was virtually destroyed (from banging from stop to stop) and had to be replaced. I'll build one. Simple, light, and low cost.

http://www.checca.net/n468acrudderlock.htm

good Idea

That rudder lock made with PVC pipe is a good idea. Is that Teflon tape on the brake lines? I know that Teflon tape is not supposed to be used on fuel lines. What about brake lines?
Joe

Thanks to everyone who weighed in on this.

Thanks to everyone who weighed in on this. My wooden box is built to the exact dimensions and when I put it in place now (post-installation), the pedals fit pretty tightly against it. The rudder hits the left stop with about 1/4 inch remaining between the left pedal (actually nut on the back that attaches the black plastic pad) and the firewall. Right pedal does not come near as close when the rudder hits the right stop. I have ordered new rudder linkages (only $2.80) and will decide whether to redo them and pull the cables tighter this time around. I think I will send a message to Van's tech support on this one first though.

Lets us know what Van's says. I;m about to this point.

Just don't poke a hole through the firewall.

It seems to me that as long as the rudder pedals are even with each other during straight flight, and as long as the rudder can be moved from stop to stop, then so what if the pedal hits the firewall when pushed harder. The firewall will prevent the pilot from over stressing the rudder control system. Just don't poke a hole through the firewall.
Joe

I ended up with one pedal a bit close to the firewall. You can twist the cable of couple of turns, back at the rudder, which will shorten the cable a bit and may be enough to allow the rudder to hit the stops before the pedal hits the firewall.

MartySantic said:

One of my friends, Al Checca, built this rudder lock for his RV6 and I think it could be adapted to the RV-12. He built it after his RV-6 was caught outside on the ground in a wind storm. Because a lock was not installed, the rudder was virtually destroyed (from banging from stop to stop) and had to be replaced. I'll build one. Simple, light, and low cost.

http://www.checca.net/n468acrudderlock.htm

Click to expand...

I built the Checca rudder gust lock. Works great in the RV-12.

[url=http://tonytessitore.smugmug.com/RV-12-Project-N577RV/RV-12-Tools-Work-Fixtures/7992519_GYr3k#918318145_LpnUo-A-LB][/URL]
[url=http://tonytessitore.smugmug.com/RV-12-Project-N577RV/RV-12-Tools-Work-Fixtures/7992519_GYr3k#918132421_FTUjD-A-LB][/URL]

Plumbing permit not required, and the cost is right!
Tony

Mich48041 said:

That rudder lock made with PVC pipe is a good idea. Is that Teflon tape on the brake lines? I know that Teflon tape is not supposed to be used on fuel lines. What about brake lines?
Joe

Click to expand...

I used it too. Just think the fuel line stuff was so that pieces didn't end up in your carb.