3D Printable Interlocked Joint

A mechanical joint that can be printed pre-assembled in one pass

3D Printing created a shockwave in the manufacturing industry and Additive Manufacturing presented a unique design pipeline with features that, if used correctly can produce parts and tools that were never possible before. One of those features is the ability to build pre-assembled parts and mechanics in a single print, a famous early example being NASA's 3D printable Ratchet Wrench that was "emailed" to the International Space Station in 2014 to be printed using ISS's new 3D printer in space. 

Inspired by NASA's wrench and other interlocking 3D printable objects, I always wanted to design something that is also printed "pre-assembled", and the opportunity arose when I needed to design a Bone Structure with Articulating Joints that would mimic the wagging/swinging motion of an animal's tail. 

I decided to challenge myself to design a mechanical joint that can be 3D printed assembled in "one go", and after many sketches and hours of 3D imagination I came up with the "donut/inverse donut" joint design that you see here.

I have an in-depth understanding of the shortcoming and advantages of 3D printers from my experience building my own 3D printer from scratch back in Tehran, so I made sure that this joint can be printed on any 3D printer without the need for supports or any other post-production procedure. 


It’s a simple design once you see how it works, but in a way it’s my love letter to 3D printing as well. because doing something great within the tight limitations of a given craft is mechanical poetry, and this is one is my short verse. 


Maker Faire 2008 NYC