I wanted to build some 3D-printed jewellery using the NASA chainmail concept I found here. It turns out I wasn't able to find a STEP model of an individual hexagonal tile, there were only STLs, so I had to model my own.

The two STEP models are for an individual hexagonal tile, one with 10 mm and the other one with 15,6 mm tile width. The models are not just scaled, the bigger one has thinner loops so you can make a lighter fabric.

I also included two STL models with examples of jewellery I designed with it, a smaller earring and a larger necklace.

Instruction for use:

Please look at the photos I included as a visual guide.

1. Decide on tile size. For jewellery, the smaller tile will probably be more useful, for larger fabric pieces use the larger one. Import the STEP file into 3D-modelling software of your choice. I use Fusion 360, the pictures are from there.
2. Make a copy of the model and place it 0,2 to 0,5 mm away with sides aligned, like the picture shows. If you have a well tuned printer, 0,2 mm should be ok, but you will have to break the print apart carefully. If you don't trust your printer that much, it's better to go with 0,4 or 0,5 mm.
3. Make a rectangular pattern big enough to make the final product. Use spacing instead of extent and keep the tiles spaced the same as in step 2. E.g. if you want to use 0,3 mm distance and you are using the 10 mm tile, then add the two together to get 10,3 mm spacing. You should get a large rectangular fabric.
4. Set select priority to “Model” and click the tiles you want to remove. Use the “Remove” option in Fusion to avoid certain possible issues with the “Delete” command. I recommend you sketch out the piece beforehand on a hex-grid paper with a pencil, it should save you some time. I found one here.
5. When done, select the whole project (or the component, if you plan on making more meshes at once) and use the right-click option “Save as Mesh” to save all the models as they are placed as an 3MF for printing.
6. In Cura, you have to first merge the individual models in the 3MF files by selecting all of them (Ctrl+A) and right-clicking command “Merge Models”. Then you can move and rotate the whole as usual.
7. Carefully break up the finished print, if necessary. If you have problems with stringing, you can remove most of it by very quickly brushing a blow-torch flame over the finished print. Careful, you can ruin it VERY quickly!