Features:

• Prints in one part
• Fits on glass bottles (Sodastream crystal)
• Fits on plastic bottles
• Easy on your printer
• Many different designs to choose from

Printing:

Choose the design you desire for your bottle type and print it with at least 4-6 perimeters (with 0.4 nozzle). If you have a 0.6, than 3 perimeters might also be enough. However, it works best if there are at least as many perimeters to make the caps “threaded area” only from walls and no infill. 

A broad band of layer hights from 0.2-0.35 (0.6 nozzle) and 0.15-0.25 (0.4 nozzle) will work for all parts.

Did some testing, regarding the material. ABS, PETG and also PLA seemed to work just fine. But i recommend using ABS and PETG for better cleaning capability. If the cap is intended to be used only a short time ( like for partys ) PLA might be fine also.

Print the optional gasket part with as many outer perimeters untill you are left with only walls and no infill. This requires FLEX filament of course. If your FLEX filament is to hard to be used as soft seal, use concentric infill, only 2-3 perimeters and 2-3 top/bottom layers. you might have to do some testing.

Assembly (Plastic bottles only):

Note: If you do not want to use the gasket out of your original cap, just print the gasket part. It has the same size as the original and will also fit into the caps for glas bottles

At first you have to remove the rubber seal from the original bottle cap. Use a tool with a soft tip, like the backside of a tea spoon, tweezers or something similar. If you use a knive or sharp screwdrivers you might damage or destroy the soft seal. 

In the second step fit the seal in the new bottle cap. If you notice some scratches on the seal, put the damaged/scratched side towards the lid and the good side towards the bottle.

Assembly (Glas bottles only):

If you do not have a Plastic bottles cap to salvage the gasket from, you have to use the optional gasket part. Put it in the bottle cap in such a way that the “print bed side" faces towards the bottle.

Note:

Because the nature of FDM prints, the parts feature grooves which are probably the worst thing to have on any food/drink related equipment. This is due to the massively increased surface area. Therefore it is harder to clean and generally loved by any type of bacteria. I use the caps mostly for pure carbonated water without drinking from the bottle directly. Since i clean them every now and then, i did not encounter any problems so far.