This is probably very well explained but I'm lacking the terminology knowledge and that's keeping me from finding the information I need.
I have a frame to which I need to attach a weight carrying arm. The arm will need to rotate vertically (1 degree of freedom) but will not be doing complete turns thus a bearing is overkill. The arm has a rectangular profile which is hollow inside, so I was planning to weld 2 small pieces of sheet metal to the frame that will form a bracket inside of which the arm will fit then drill a hole and put a bolt through but I'm afraid that due to the vertical rocking motion the bolt will quickly come loose.
What would be the proper solution in this case?