Ensuring pin joint behavior in structures systems

Reducing moments at structures joints

To ensure that joints within the items that use the beams from the various structures systems behave as pin joints (do not support torques or moments) around the axis of the screws, advance the screw into the constructed joint only finger tight.  Then, back out the screw by a 1/4 turn so that there is no significant friction between the surface of the beam and the joint to which it is attached.  The related video linked to below shows this process.

Note: If the structure is going to be subject to cyclical loads or repeating loads, please check to make sure that the screws are not backing out further under the action of the oscillation.  If this is occurring, please tighten down the screw to finger tightness to prevent the screw from backing out during the use of the oscillating or repeated loads.