Botte Thread PP28

I didn't find an adapter part for a bottle thread (how lemonade/water bottles are sealed here in Germany) to use to attach a 3d print to a bottle, so I did some research, found out that the norm is called PP28 or din 6094-7 and designed one.
It fits tight without any play on my testprint.

Please contact me if you need other formats, as this is expected to be used as part of a bigger print.


## CAD construction guide:
> This is for Fusion360, but your CAD software will work similar I guess (except OpenSCAD)


* Create two circles of 28 mm inner diameter and outer diameter of your choice (mine is 31 mm)
* Extrude for 11 mm
* Create an offset plane to the axis plane of the circle, with 1 mm offset
* Create a coil with the offset plane as basis, parameters:
* Diameter: 3.5
* Revolutions: 2.5
* Pitch: 3.5
* Section: Circular
* Section position: On center
* Section Size: 2 mm
* Operation: Join