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A better rod end bearing retainer

Very clever! I used some of those very small diameter but thick washers to get space, and then a large diameter washer, as shown in the plans, but this is a much more elegant solution.

I do the same thing that Mickey does.
These Pegasus Racing washers are $1.80 each. And heavy. Of course, you don't use very many of them, so in the big scheme of things, they are not a bad choice.
 
This is what I did. It's made of .020 and is adequately strong - potential side loads on the bearing are small and quantifiable. I just could not imagine putting in something heavy where the weight wasn't needed.

Rod End Retention 1 S.jpg

Yeah, they take a minute to make. Not much longer, though. Hint, drill the hole first, then cut out the outline and deburr.

Dave
 
Vans is best?

I like the Vans way of retaining rods end the best; using a steel oversized washer. If the rod end bearing were to fail and the retaining washer/metal had to do its job, I can see where the controls would be bound up and there could be quite a bit of force pushing on the retainer as the pilot tries to unstick everything.

When I was a kid flying gliders, a few glider pilots had experiences at altitude in wave, where the controls iced up. They said it took considerable force, applied over a few minutes, to break the ice and restore limited control movement. For us, the Van's planes are capable of flying high enough to be above the freezing level, so iced up controls may be a potential situation.

I think something more substantial than 0.020" aluminum is necessary. I think I am sticking with the Vans design.
 
This is what I did. It's made of .020 and is adequately strong - potential side loads on the bearing are small and quantifiable. I just could not imagine putting in something heavy where the weight wasn't needed.
View attachment 34033
Yeah, they take a minute to make. Not much longer, though. Hint, drill the hole first, then cut out the outline and deburr.
Dave

Don't forget to tighten that jam nut! (I assume that's what the blue tape is for.)
 
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John, the axial forces in the pushrods can be quite high (although not at this aileron servo). But the side loads aren't. The angles are too small.

Mel, it's done. Thanks for the reminder!

Dave
 
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