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RandyL
10-31-2008, 07:18 AM
The rudder pedals!! Cleaning out the welds and getting the tubes to rotate freely, wore me out!

Jorge,

What steps did you take to get the rudder pedals to move freely? Coincidentally that's what I'm working on now. This weekend I plan to take a brake cylinder hone and ream out all tubes that ride on the plastic bushings to reduce friction. I'm still struggling with what the best lubricant to use is though. Anyone have any recommendations?

kmul
10-31-2008, 10:43 AM
randy, if you use a brakecyl hone like i started to it will clean the tubes up and get rid of the powder coat but if you use it to clean out the weld i think you may end up making the other side of the tube too thin. i think its only 035 tubing. use a dremel on the welds first. the real problem is that the tubes are slightly bent from the welding. i ended up heating mine and straightening them first. they then went together like a hot knife thru butter. kf had suggested i might need to sand part of the bushing thinner but i didnt like that approach. also if you sand the powder coat down, the bushings go on without splitting them like the manual says to. after hours of work mine would not go together until i straightened the tubes. anything will lube the brake hone.

Jorge&Cindy
10-31-2008, 02:23 PM
For the welds deep inside the tubes, I have a friend who loaned me an extension for a grinding stone. I mounted it to my drill press and that allowed me to reach the welds inside. As for the bushings, I had to "work" them down a bit. I used fine sand paper and a Scotchbrite pad. I would assemble everything moving the tubes around and around. I would take it apart and used the pad to wipe down the bushing till it looked clean(they would come out a little dark after turning the tubes). I kept doing this and little by little the would rotate freely. Just be careful forcing them in. My left side pedals got suck and it took a lot of effort and ruining one bushing to get them apart. You do need to get the powder coat out of the tube, just don't make them too thin. I used LPS 2 to lube all the innards. I also took almost all the powder coat off the inner tube so the it would not rub the outer. My outer tube was also slightly bent, but It managed to work out. I have both sides mounted and it's like butter.

On a side note: Randy, looking at your build site, your pedals are in, or am I missing something?


http://img261.imageshack.us/img261/7436/dscf2447au7.jpg (http://imageshack.us)

airlina
10-31-2008, 02:55 PM
Jorge,

What steps did you take to get the rudder pedals to move freely? Coincidentally that's what I'm working on now. This weekend I plan to take a brake cylinder hone and ream out all tubes that ride on the plastic bushings to reduce friction. I'm still struggling with what the best lubricant to use is though. Anyone have any recommendations?

Make sure that you have the pedals moving freely not only on the bench, but also after they are installed in the cockpit. When I did mine, I got them working freely on my work bench, but once I torqued the torque tube fittings in place they started binding- so out they came for a redo. This step is extremely important,because any friction in the rudder pedal system will cause you grief once you start flying the finished product. Refer to the previous discussions on rudder trim. If the rudder is deflected even a small amount due to system friction your airplane will be uncoordinated after each rudder pedal deflection because the rudder will not recenter. Bruce N199CL

Jorge&Cindy
10-31-2008, 04:40 PM
Hey Bruce, you too?
I think when you torque the screws down on top the plywood floor, the brackets must be flexing out of alignment. My were fine on the bench and had to come out for a little more work the first time I mounted them.

RandyL
10-31-2008, 05:59 PM
Hey guys, I moved this discussion of rudder pedal friction to its own thread so it can be found in the future. There's some good info here and I don't want it to get lost.

Cheers,

RandyL
10-31-2008, 06:05 PM
Randy, looking at your build site, your pedals are in, or am I missing something?

The previous owner installed them but I didn't like the considerable friction so I took 'em apart and started over. I needed to cut off the horns to convert them to adjustable style and drill lightening holes in the pedals themselves anyway. This required me to get all the parts re-powercoated. All the parts were gray, they will now be white with the pedals black.

So I guess the lube of choice would be LP2 for all control connections including these plastic bushings against the steel tubes?

kmul
11-01-2008, 06:15 AM
the plastic bushings are the same as the flaperon bushings i think. in the wing section of the manual there is a caution against certain lubricants with aromatic components. i had used some rotella grease on one side before i saw this. emailed john and he said that it was ok but that his preference in this spot was white grease. which i used on the other side. both sides have a very smooth action with the white grease side a hair smoother.

Dick B in KY
11-01-2008, 06:22 PM
Nice to know I'm not the only one having this problem with friction. Thought I was going nuts trying to free up the pedals. Finally put them in a press and un-sprung them. Have not hard mounted them yet so may have more work to do. I used a long round file to clean out the welding slag on the inside and also removed all powdercoat. I used lithium grease on mine. Great minds think alike.:)

Dick B

Dorsal
11-03-2008, 06:32 AM
For what it's worth I had to shim my outboard bracket to get it to remain square after I torqued it down.

Sabre
01-15-2014, 10:13 AM
Perused everything I could find on the rudder pedal installation but I still had question concerning the torque tube and inboard rudder pedal. Is the torque tube suppose to rotate in bearing and the bearing rotate on the torque tube or does it matter? The manual states to sand the torque tube to achieve smooth rotation so I'm assuming the bearing rotates with the inboard rudder pedal and the torque rotates within the bearing. Thanks

PapuaPilot
01-15-2014, 10:02 PM
I had the same problem with my rudder tubes. I ended up filing and grinding out the inside of the tubes due to the welds coming through. I also sanded and filed down the bushings until everything turned smoothly.

When the bushings turn good on the bench make sure they do the same when mounted in the plane. Slide one end in the bushing, rotate it and find the position where it turns smoothest. If this is not perfectly lined up (i. e. the opposite bushing and bracket needs to be resting on the airframe mounting point) then your tubes are warped and need to be straightened. Once one end is smooth you need to do it to the opposite side.

This will take a lot of time, but like others have mentioned, you want to have the whole system moving smoothly.

I don't think it matters whether the bushing or tube rotates.

n85ae
01-15-2014, 10:51 PM
That's the trouble I had. The mount points were not square, so washers and
shimming to the rescue.

Jeff


For what it's worth I had to shim my outboard bracket to get it to remain square after I torqued it down.

Sabre
01-16-2014, 02:20 PM
Thanks for the posts from all on this subject. After reading through all them a couple times and inspecting my respective parts I found that most of my time was spent truing the parts. Where the horns are welded on to the tube distorts the tubing causing it to be out of round - I was able to use hand clamps to press them nearly round and then with a file while removing the slag I also removed small amounts of material to make the tubing round (a lot of measuring). I also found that 3 of the bearings were nearly identical but the fourth one was thicker causing the ID to be smaller. I polished this one to match the other three. Once all parts were true (again a lot of time measuring pretty precisely) things went together pretty smoothly. I did not have to do much sanding to get the desired fit or cut the bearings (still need to install though). I also found that any high spots in the PC (OD) or inside the tubing showed up on the torque tube (bearing material rubbed off, requires continuous cleaning of parts) indicating where material needed to be removed. Also doing a initial polishing the ID of the bearings helped a lot to remove slag/roughness in the bearing that would get deposited on the tubing making it sticky and hard to turn. If the bearing does gets suck on the tubing isopropyl works great a temporary lubricate to remove them without any messy clean up. Hope this helps future players!

Sabre
02-06-2014, 11:41 AM
After working on getting the seat pan installed so I can decided on placement of the rudder pedals that will be most comfortable for me I did a final inspection of the rudder pedals before committing them to riveting them together. I have to say I'm a little concerned with the plastic bearing rubbing against the weld for the rudder horn as well as the spacing of the head of the clevis bolts holding the pulley (adjustable rudder pedals). The weld at the rudder horn is less than smooth and seems like it will cause increased rate of wear at the bearing resulting in potential future binding of the clevis bolt heads. I've thought of adding a thin spacer between the weld and bearing of the torque tube and inboard rudder pedal tube. Am I bearing overly concerned here? The assembly seems a little questionable to me? Appreciate any thoughts on this.

PapuaPilot
02-06-2014, 01:00 PM
A picture of what you are talking about might be nice.

I don't think you are wrong to be concerned about potential friction or rapid wear. If there is any chance of interference in the future it would be best to take care of it now.

Sabre
02-06-2014, 01:46 PM
Attached are pics of the spacing between the heads of the clevis bolts and weld at the horn bearing location. I knocked down the high points of the weld but it still is not exactly a smooth finish. Seems the weld is needed to keep a minimum spacing for the clearance of the bolts heads. Maybe a filet of Hysol?

Sabre
02-09-2014, 02:28 PM
Just as a reference point is everyone else's rudder horns welded on the side that the bearing flange is? Is this a normal bearing flange to weld rotation point? Thanks

PapuaPilot
02-09-2014, 03:00 PM
I finally got a chance to look at mine. The welds are on the same side and the bolt head clearance is similar.

Jerrytex
03-18-2019, 03:35 PM
I am putting my rudders together and I am running into some of the issues described here. I cannot get the thin bushings between the inner rudder torque tube and the outer torque tube to go in. I will say that I had to build the inner pedal assembly. I have the outer rudder pedal assemblies and took the the dimensions from that so I used the exact size. Does anyone know if the tubing on inner pedal assembly is a different size as the outer pedal assembly? The pictures that I have seen shows that it looks like the same size tubing on both pieces? I feel like I can sand the inside more but it's only .035 and seems like there would not be much "meat" left.

jmodguy
03-18-2019, 06:40 PM
I took a slightly different approach. Seemed ridiculous to have a plastic bushing turning in a tube. I drilled out the plastic part and inserted a bushing about 1/64” longer than the plastic. The plastic fits snug in the tube and the assembly rotates very smoothly around the bushing.
21924

Jerrytex
03-18-2019, 07:05 PM
I can get the end cap inner torque tube bushings in no problem. Its the thin ones between the inner and outer torque tubes that I am having a hard time with. I put some calipers on the tube and I have actually only taken .005 out. Measuring the bushing it shows I need an additional .005 to fit, so .010 total. I think I'll be ok removing .010. The sidewall is .050. Might split the difference and take some off the inner torque tube and some out of the outer tube.

I also do like that idea of the extra bushing.

efwd
03-18-2019, 09:14 PM
I don't really know if I am understanding you but.......
I am thinking of the bearing that is supposed to be cut across one side of it as is stated in step 10 of the that process. Any chance that is what you are speaking of?

Jerrytex
03-19-2019, 05:29 AM
21925

I split the bearing and it's still tight. I mainly want to verify that torque tubes are the same size.

Jerrytex
03-19-2019, 05:31 AM
21926

This is the assembly that I am working on.

PapuaPilot
03-22-2019, 02:06 PM
As others have stated you need to get these bushings to be as free as possible, but without extra slop. Besides getting the dimension right by sanding the bushings you also need to make sure the tubes are aligned to each other and perfectly round. I recall that my rudder tubes were slightly out of round and warped, which probably happened when the other pieces were welded on.

Jerrytex
03-25-2019, 12:41 PM
Apparently welding on the tubing caused them to shrink a bit. A friend of mine has a machine shop so after some milling, stretching, sanding and fitting, I got the bushings in and all is smooth now. Thanks for the replies.