May 10, 2015

3D Printed Alphabet Bracelet Links

After some experimenting with snap together parts, I came up with a design which works pretty well for bracelets and other small applications. (Links to the model files are at the bottom of this post). I call these abclets.
The personalized bracelets were the hit among young kids like my daughter (who is a 3rd grader) and seemed also to be a great project for in-school printing, since the parts are small and quick to print. I'm making the whole alphabet of links available here and as well as a couple of blank template links which you can use to make your own links.

Printing Notes

These work best when printed at full scale, which is still pretty small - 15mm X 15mm per link on the main part of the link, with a total width of 25mm per link including the linkage parts. That means every two links basically measures 45mm wide since there is overlap of the linkage. It takes about 7-8 links to fit around a small wrist (3rd grader), and 9-10 links for an adult.
I've had pretty good luck scaling these down to 80%, but they fit together very tight at that scale and take much more cleaning up after printing to connect and move loosely as a bracelet.

How The Links Connect

There is a unique, custom connection design used here. The parts can only be connected at a 90 degree angle, which makes them harder to come apart when you're wearing them on your wrist. But to get them together, you have to understand the connector.

Instructions for connecting Snap-Together Parts. Reverse the process to un-snap them.

Using these in School

These Alphabet Links print pretty quickly, making them a great in-school 3D Printing project. One of the most common problems I hear about 3D Printing in school is the time it takes to finish a project and for each kid to finish printing their own object. These letters can be a quick win, giving you the opportunity to print one every 10 or so minutes. Kids can see (and take home!) results on the first day and even team up to finish whole projects rather quickly. Given that the links are made to fit together, it's a great collaborative project too. I'll soon be posting ideas about specific projects you can use these for in school, but until then, share your own ideas by adding here in the comments!

The 3D Models

I have made a separate STL file for every letter. This allows me to quickly gather just the letters I need for a given project into one print project in my slicer software (I use CURA these days). I've also got the whole alphabet here in one STL for those who are ambitious and pretty confident in their printing and actually need all the letters at once. I have yet to print all at once.

>  The whole Alphabet as one .STL File (on

>  Link to every individual letter (so you can just download the ones you need for a given project).


  1. I'll be honest, I wasn't sold on this project until I saw your connector there. That's cool. That's brilliant.

    1. Thanks Joseph! I was really pleased with it, and have tested it pretty well now wearing the bracelets (me and my 9yr old daughter) for extended periods. Lots more to come here...