Improved Ball and Socket Joint for PCB Workstation

cults3d

This is an advanced ball and socket joint for giufini's superior PCB Workstation with Articulated Arms. The author employed HIPS for his ball and socket joints, yet I only print with PLA and PETG. With both materials, I encountered a multitude of problems getting the articulated arms to function well. Here's a concise summary of the issues I faced: The socket ball wears down rapidly and the articulated arm becomes extremely loose. The ball easily dislodges from the socket when the travel limit of the arm is reached. The arms don't bend with a very tight radius, so moving the arm around frequently causes the balls to pop out. I attempted both versions of the alternative ball and socket design with heat shrink tubing, but the heat shrink quickly deteriorates and gums up the socket. Additionally, the bend radius is also diminished with the heat shrink. So I took a stab at designing an improved ball and socket joint. The primary requirement is that the ball remain unchanged in size so it fits all of the accessories in the original project. Here are the mods I made to the design: Raised the ball away from the socket by about 2 millimeters - this significantly improves the arm bend radius and also makes it much harder for the ball to dislodge from the socket when the travel limit of the arm is reached. Made the socket envelop the ball approximately 1 millimeter farther down - this causes the ball to stay in the socket better and also enhances the stiffness of the arm with a greater surface area in contact. Modified the inside diameter of the socket slightly smaller to stiffen the joint and prevent it from loosening as much I'm extremely pleased with the final result. All of the probe holders and accessories I printed still attach fine, but I no longer experience problems with loose arms and balls popping out.