Abstract: Self actuating mechanical joints that utilize pivotally mounted clamping levers (114) linked to a displaceable catch (112). The displaceable catch engages an external beam (126) inserted into the joint and thus initiates the clamping levers to clasp around the beams profile. Mechanical integrity between beam and joint is achieved when the displaceable catch locks with a stationary catch (102) at the instance the beam is fully inserted into the joint. The three joint designs presented in this patent are the Lever Latch (99), Lever Clamp (299), and Trunnion Clamp (499). Together, they allow mechanical parts to be joined under the following respective circumstances: beam element connected to beam element along their centerline axis, one beam element connected perpendicular to another beam elements centerline axis, and flat plat connected to another flat plat.