A snap-together printed chain from bracket, spacer and connector parts.
3D Printed Bike Chain by Open-Source-Imports
https://thediyjunky.com/@open-source-imports/printed-bike-chain
Licence: CC-BY-SA-3.0
Adapted from: https://www.appropedia.org/Bike_Chain
Original author: User:Mlfraser
Original licence: CC-BY-SA-3.0

A bicycle chain assembled entirely from 3D printed brackets, spacer rings and connector brackets that snap together.
| Part | Size / spec | Qty | Unit cost |
|---|
Required total: $0.00

Take two main brackets, and place a connector bracket, spacer ring, and another connector bracket on the cylinder of one of them.

With the assembly just made, place the cylinder of each of the main brackets inside the larger hole of the other.

Pull on both brackets to snap them into place of the smaller hole.

Take 2 more main brackets, 2 more spacer rings, and 2 more connector brackets. Place a spacer ring between two connector brackets.

Assemble the other main bracket with a connector bracket, a spacer, and another connector bracket.

Snap the assembled main brackets together as before.

Continue this process until just two main brackets are left. Place a spacer between the connector brackets at the join to close the chain.