Rod End Bearings Tip

[wirejock]

Rod End Bearings.
Sends a shiver down the spine doesn't it?
The idea of trying to put a bolt through a part, then slipping one of those tiny washers on, then slipping the bearing in without the washer falling off, then somehow slipping another mini washer in place. All while laying upside down folded up like a pretzel using one hand. OMG! The last two days my cuss jar filled up enough to buy my beer for the rest of the year. I actually told Sweetie she doesn't want to come in the shop today.
All the tricks are cool. Fishing line, tape, super glue, washer wrenches, whatever flavor you like. Go for it. Actually, a washer wrench with a piece of tape over the edge of the washer, really worked well. When the washer popped out of the washer wrench, the tape held it in place.
However, a little forward thinking might just save you some heart ache. Just install the rod end bearings before installing the component. Duh!
The side by side control stick weldment for example. There's no reason why those rod end bearings can't be installed while it's being assembled on the bench. Any control rods will just screw right on. The pitch bell crank is another. Add the rod ends before installing it. The rods will screw right on. Same for the aileron rod end bearings on the bellcranks and servos. Uggg. I wish I thought about it a long time ago.
If the bearings are in the way or need to be removed, that's far easier and won't cost a six pack in the cuss jar. They come right out and a magnet will snag any parts that fall.
Enjoy my friends. That's the point, right?

 

[PaulvS]

What's next

Ummm maybe it's just me, but I needed to refit the control linkages multiple times to adjust the rod lengths when rigging the controls. This included setting: sticks parallel, aileron positions and elevator position with stick neutral. There was a bit of back and forth between adjusting, refitting, checking and repeat until it was right. I left the washers out while adjusting the lengths.
Don't forget your jam nuts!

 

[wirejock]

Adjustment

Ummm maybe it's just me, but I needed to refit the control linkages multiple times to adjust the rod lengths when rigging the controls. This included setting: sticks parallel, aileron positions and elevator position with stick neutral. There was a bit of back and forth between adjusting, refitting, checking and repeat until it was right. I left the washers out while adjusting the lengths.
Don't forget your jam nuts!

That's my point. Install the bearings with the correct hardware.
Mark the rod. Need a little more or a kittle less? Just run it in or out a few more turns before screwing it into the opposite bearing. Simple to count turns and get the right lengrh instead of fighting with bearing install. Just my humble aggravation!

Yes, Jam nuts go on first.

 

[PaulvS]

That's my point. Install the bearings with the correct hardware.
Mark the rod. Need a little more or a kittle less? Just run it in or out a few more turns before screwing it into the opposite bearing. Simple to count turns and get the right lengrh instead of fighting with bearing install. Just my humble aggravation!

Yes, Jam nuts go on first.

Where are you up to. i.e. have you got all the rods finally fitted and the controls fully rigged, or are you just starting assembly?

In my experience the rods needed to be fully assembled and adjusted before final fitting with the washers. So there is going to be a fight with the washers in situ. For the ailerons the fight is going to be either up in the wing at the bellcrank, or under the seats on the control column. For the elevator pushrod, the fight is either at the bellcrank end or at the control horn end. The elevator control horn end is harder to reach because access is so tight in the back of the tail cone.

And YES, it is frustrating!

 

[wirejock]

Rigging

Where are you up to. i.e. have you got all the rods finally fitted and the controls fully rigged, or are you just starting assembly?

In my experience the rods needed to be fully assembled and adjusted before final fitting with the washers. So there is going to be a fight with the washers in situ. For the ailerons the fight is going to be either up in the wing at the bellcrank, or under the seats on the control column. For the elevator pushrod, the fight is either at the bellcrank end or at the control horn end. The elevator control horn end is harder to reach because access is so tight in the back of the tail cone.

And YES, it is frustrating!

I haven't final rigged. That said, I will gladly fight with a bearing in the wings or tail than laying down on the floor of the fuse. Maybe a huge mistake, but I'll take my chances. Like I said, they much easier to remove.

 

[Roadjunkie1]

Tiny unseen spaces.....

Rod End Bearings.
Sends a shiver down the spine doesn't it?
The idea of trying to put a bolt through a part, then slipping one of those tiny washers on, then slipping the bearing in without the washer falling off, then somehow slipping another mini washer in place. All while laying upside down folded up like a pretzel using one hand. OMG! The last two days my cuss jar filled up enough to buy my beer for the rest of the year. I actually told Sweetie she doesn't want to come in the shop today.

Here's how lucky I am: I had futzed with just that back in the tail trying to hook up the elevator push rod I had take out to access the inside of the fuselage. I tried everything I knew through that TINY little access hole (who made that hole THAT small?? Oh, yeah: Me....)

Sweetie comes home and I ask if she would help. 15 minutes later she had everything in place including all those washers in order. nut on, ready for the cotter key. I had to look to "approve" the installation but mostly to amaze myself she had done in 15 minutes what I tried to do for what seemed like several hours..... Tiny hands come in.....well, handy sometimes.....

 

[Bavafa]

When I hit that point in the jar, I calm myself by saying; If it was easy, everyone would be doing it
Somehow it helps me.

 

[Richard Connell]

I haven't final rigged. That said, I will gladly fight with a bearing in the wings or tail than laying down on the floor of the fuse. Maybe a huge mistake, but I'll take my chances. Like I said, they much easier to remove.

You may get lucky, but having done it half a dozen times, it’s just not that simple.
You may well be disappointed if you anticipate not having to adjust rod ends in difficult to access places.
More importantly… whatever happens, please don’t cut any corners. Do whatever is required to meet book values for throws, rod end thread engagement, rubbing, etc etc.
Adding to Paul’s point, I can tell you for sure that there isn’t enough thread on the stock rod ends to satisfy all requirements by adjusting from one end only unless you miraculously get it super close first go.
Maybe this is possible on one of the 7 pushrods.
So you will be pulling them off at both ends (most likely the long aileron pushrods) regardless of what you think currently.
You will likely curse.

 

[wirejock]

Adjustment

You may get lucky, but having done it half a dozen times, it’s just not that simple.
You may well be disappointed if you anticipate not having to adjust rod ends in difficult to access places.
More importantly… whatever happens, please don’t cut any corners. Do whatever is required to meet book values for throws, rod end thread engagement, rubbing, etc etc.
Adding to Paul’s point, I can tell you for sure that there isn’t enough thread on the stock rod ends to satisfy all requirements by adjusting from one end only unless you miraculously get it super close first go.
Maybe this is possible on one of the 7 pushrods.
So you will be pulling them off at both ends (most likely the long aileron pushrods) regardless of what you think currently.
You will likely curse.

I am having trouble understanding.
Why can't I remove one bearing? Say the right aileron bellcrank bearing and just rotate the rod in or out of the control column bearing then screw the aileron bellcrank bearing back on a defined number of turns?
Why do both bearings have to come off?
I must be missing something?

 

[PaulvS]

You can do one bearing at a time.

There is no need to count turns in my experience. Installation is an iterative process and really the most difficult part was getting the small washers on after the rod has been adjusted to the right length. (There is a need to work in tight places, work upside down, crawl into tailcone etc. so it helps if we are fit and lithe).

Per post #1 you can pre-fit one of the rod end bearings "A" along with its washers to the bellcrank or column or horn (but cannot fit both ends as I interpret in the aileron example). Spin the tube onto that bearing.

Next thread the other rod end bearing "B" into the other end of the tube. The overall length is adjusted by turning this bearing in or out. Check the overall length by inserting "B" into its fork and then slip it out to adjust as required to get the bolt holes to line up (with the stick pinned neutral and the bellcrank pinned neutral). Once the overall length is right the washers can go in.

Final step is to spin the tube left or right to ensure adequate bearing threads are engaged at both ends. Then tighten the jam nuts.

The above assumes the tubes have been made to the correct length.

The rest of the process is to check for binding, specified deflection range etc.

 

[Biggiesauls]

my trick

my trick.... small hands and (fuel) lube.

 

[wirejock]

Bearing

You can do one bearing at a time.

There is no need to count turns in my experience. Installation is an iterative process and really the most difficult part was getting the small washers on after the rod has been adjusted to the right length. (There is a need to work in tight places, work upside down, crawl into tailcone etc. so it helps if we are fit and lithe).

Per post #1 you can pre-fit one of the rod end bearings "A" along with its washers to the bellcrank or column or horn (but cannot fit both ends as I interpret in the aileron example). Spin the tube onto that bearing.

Next thread the other rod end bearing "B" into the other end of the tube. The overall length is adjusted by turning this bearing in or out. Check the overall length by inserting "B" into its fork and then slip it out to adjust as required to get the bolt holes to line up (with the stick pinned neutral and the bellcrank pinned neutral). Once the overall length is right the washers can go in.

Final step is to spin the tube left or right to ensure adequate bearing threads are engaged at both ends. Then tighten the jam nuts.

The above assumes the tubes have been made to the correct length.

The rest of the process is to check for binding, specified deflection range etc.

That makes complete sense. Exactly how I expected. Thanks. The only one I see as a fight is the one from the control weldment to the pitch bellcrank. One end or the other will have to come off for fine tuning. I'll have to pick my pain!

 

[nohoflyer]

Speaking of the rod end bearings, did anyone fabricate and install the elevator pushrod prior to attaching the empennage?

 

[wirejock]

Rods

You can do one bearing at a time.

There is no need to count turns in my experience. Installation is an iterative process and really the most difficult part was getting the small washers on after the rod has been adjusted to the right length. (There is a need to work in tight places, work upside down, crawl into tailcone etc. so it helps if we are fit and lithe).

Per post #1 you can pre-fit one of the rod end bearings "A" along with its washers to the bellcrank or column or horn (but cannot fit both ends as I interpret in the aileron example). Spin the tube onto that bearing.

Next thread the other rod end bearing "B" into the other end of the tube. The overall length is adjusted by turning this bearing in or out. Check the overall length by inserting "B" into its fork and then slip it out to adjust as required to get the bolt holes to line up (with the stick pinned neutral and the bellcrank pinned neutral). Once the overall length is right the washers can go in.

Final step is to spin the tube left or right to ensure adequate bearing threads are engaged at both ends. Then tighten the jam nuts.

The above assumes the tubes have been made to the correct length.

The rest of the process is to check for binding, specified deflection range etc.

Speaking of the rod end bearings, did anyone fabricate and install the elevator pushrod prior to attaching the empennage?

I did. Elevator and Aileron rods. I cut them a little longer because I read quite a few posts where builders came up short. Can't remember the exact extra. Seems like 3/8". I figured I can take up 3/16" on each bearing easily. Inalso cut the two aileron to bellcrank rods a little longer. I remember that one was cut in half and both halves used without trimming. I did rig everything once during construction so they should be pretty close. I also remember rotating every rod all the way both directions to be certain they couldn't fall off.

 

[PilotjohnS]

Not that bad.

For me this wasnt that bad. I did put the center rod in, between the two sticks, on the bench. But using super glue to glue the bushings to each ball joint wasn't that bad. Just had to make sure my hands were greaser than the parts, otherwise the plane became permanently attached to me.