After Servo Modification

[spectrem12]

I modified my 2 servos. Before I put the lids and screw them shut I tested them to see how they worked. They work great, but as soon as I screw the lid on, they rotate 360 degrees 4 - 5 times then do a quick 180 turn counter clockwise then back to continuous clockwise. They sometimes even begin to slow to a stop like the power source is dieing. But as soon as I take the lid off, they work fine again.

Any ideas? I have checked to make sure the gears are clean. They seem they should be fine.

[photomark]

you must be pushing something out of place as you put the lid on .

It may be a shaft or gear that is getting pushed out of alignment and then pushing on another gear or shaft .

as it only happens when you put the lid on then this is all it can be .

[Soeren]

Hi,

[...] as soon as I screw the lid on, they rotate 360 degrees 4 - 5 times then do a quick 180 turn counter clockwise then back to continuous clockwise.

Do they repeat this every time, same pattern and does the reverse happens more than once in the same go?

They sometimes even begin to slow to a stop like the power source is dieing. But as soon as I take the lid off, they work fine again.

Sounds like some interaction with the control electronics, perhaps via the potentiometer that you cut or glued?
Did it move in-between lid-offs?

I have checked to make sure the gears are clean. They seem they should be fine.

You didn't clean off the servo grease, did you?   

[spectrem12]

I did not clean off the grease.

I should probably put a little more on them just in case though.

There is a slight pattern. 4 or 5 full rotations then 1 half rotation the other way. Give or take.

And it's the top lid to the gears. Not the bottom, so I do not think it is the electronics.

But I am guessing I have to be hitting something in the gears when putting the lid on. Or the gears are still dirty. Its just odd behavior

[paulstreats]

what did you do with the potentiometer? did you glue it, replace it with resistors or did you just remove cut off the stick that goes in it and leave the potentiometer unglued.

The reason i ask is that a hard edge may be catching it occasionally or maybe turning it still with friction but only at certain points of the rotation.

[spectrem12]

I replaced with resistors.

[waltr]

I'd look for something shorting out when the cover is put on.
Try poking around to see if it'll act bad.