I am looking for a better Pivot point design for linkages

[TastyAndrew4688]

My current set up I have 2 3d printed levers that are connected via a pivot point that Is made from a bolt, washers, and a nut, However for my purpose I would like for the levers to be able to be moved by hand, but then be able to retain any position I leave them in. As you use the current levers you would have to retighten the nut and bolt so that the position would be sustained. how can I fix this issue? Bolt->washer->lever->washer->lever->washer->nut

 

[3DDave]

This is typically done with a spring washer to provide a constant preload and then friction to hold it in place. However that limits the resistance to turning but it is how shift levers on bicycles used to work.

An alternative is to use an over-center locking lever, much like the quick-release on a bicycle seatpost or axle so that only one hand (or thumb) is required to rapidly release and reapply the squeeze required to hold position.

As a final shot, one could replace a nut with a threaded knob, making tightening the joint by hand simpler. You need to find a way to keep the bolt from turning. Without a picture that is difficult to make a recommendation for.

 

[mfgenggear]

maybe use two nuts and a washer.
first nut to hand tight enough to cause slight friction. then install second nut . retain first nut with a wrench. then torque second but prevent the first nut from moving.

 

[IRstuff]

You can use Belleville washers, or a stack of them, depending on how much resistance you want.