We’re not exactly sure what kind of shenanigans [Conrad Brindle] gets himself into, but apparently it often requires cylindrical couplings to attach 3D printed parts to each other. He found himself designing and redesigning this type of connector so often that he decided to just make a parametric version of it that could be scaled to whatever dimensions are necessary for that particular application.
In the video after the break, [Concrad] explains the concept behind the coupler and how he designed it. Put simply, the tabs inside of the coupler are designed to grab onto each other once the coupler is spun. When he demonstrates the action, you can see that both sides of the coupler are pulled together tightly with a satisfying little snap, but then can be easily removed just by rotating them back in the opposite direction.
The nature of desktop 3D printing means that the female side of the connection requires support when printing, and depending on your printer, that might mean a relatively rough mating surface. [Conrad] notes that you’ll need to experiment a bit to find how small your particular machine can print out the design before things get too gummed up.
We can see how this would be useful for some applications, but if you need a printed joint that can handle a decent amount of torque before giving up the ghost, you might want to look into (mis)using one half of a spider coupling.