This Cuban chain model is setup in a fully parameterized fashion, so that you can open it up in Fusion360 and change it to be whatever length or shape you need.
Two versions are provided. The spiral approach allows for an impressively long length of chain to be printed at once (e.g. a chain around 3 meters in length is possible in a single print on an MK4!). Or, a secondary version has now been added that will generate an attached chain loop.
I've included the STL files for the basic/default chain link style at several different lengths here with the model. For the most fun though, you'll want to try opening up the attached “Cuban Chain.f3d” file in Fusion360, so that you can generate your own STLs.
Here's a quick video showing how that works:
For those that want an even longer attached loop chain, a bonus chain version has now also been added:
The author marked this model as their own original creation.