How do you fix a revolve joint?

Hey!
Sorry is this is a silly question, but I have these two parts (from a gripper I am designing) that need to revolve against each other (simpler than it sounds, check the image). I used a simple screw and nut and (as expected) it becomes loose after few movements. Essentially the parts unscrew the nut. What is the easiest way to overcome? The only thing I am aware of are the nyloc nut but I don't think it is the correct solution.

Thanks!

You can use a nylstop nut or loctite, or try two nuts.

Tried the two nuts but again they unscrew after the second or third movement...

demetris Wrote:
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> Tried the two nuts but again they unscrew after
> the second or third movement...

Tighten the nuts against eachother.

Oh I see! IT WORKS!!!
Thanks guys! Seriously thanks a lot!

Demetris

NewPerfection Wrote:
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> demetris Wrote:
> --------------------------------------------------
> -----
> > Tried the two nuts but again they unscrew after
> > the second or third movement...
>
> Tighten the nuts against eachother.

if you want it to work reliably over a long time and thru temp cycles you will want to tap the nut on one of its 6 sides and place a grub screw in an tighten it down. It will lock the nut in place. Even better drill thru the nut and bolt, and place a pin.

if you need reliability, or it hinges a device that prevents something dropping or moving, these next steps are preferred.