Ball and Socket Joint Based Helping Hands

thingiverse

I designed a ball and socket joint inspired by https://www.thingiverse.com/thing:889439 to help me with a helping hands project I wanted to create. I took a different approach to the design and added dimple and detent system that allows for many different angles while reinforcing rigidity. The STL file versions included have a 2.5% increased ball vs socket size. This is to maximize surface contact area to increase friction. I use this value with PETG, but you may wish to experiment with lower and higher values to determine what works for you. The grippers should be printed with one of the flat sides on the ball down and with support on build plate only. They can be a little difficult to remove from the supports, so I recommend printing one more than you need. I break about one in ten during support removal. The base can take an arbitrary number of sides, I just set it to 6 to match the hex theme I chose to decrease material used. The render time in OpenSCAD is excessive because of the resolution included. You can probably reduce $fn to 26 or less and get away with it. I tried a number of patterns for the dimpling, and what I have is definitely not the correct way to do them, but I really didn't want to spend another couple days thinking about dimples. Libraries used include the scad-utils library found on github at https://github.com/openscad/scad-utils