Parametric MasterSpool with thread

Hello, I'm using a Prusa i3 MK3 3D-Printer and refill filament from http://www.dasfilament.de.
The refill filaments saves plastic and shipping weight/costs. To use it, I will need a master-spool. I found several, but no one met my requirement, e.g. customizing the rod hole diameter or using less material and printing time. So I decided to make my own thing, starting with an other thing: https://www.thingiverse.com/thing:1782398
My thing is fully reconfigurable using openscad (http://www.openscad.org), so it's usable not only as a master-spool and there is no need to glue anything.
You can change anything for your needs and make a remix of it.
I hope it`s for everybody useful. Please give me a comment, if you have some questions, remarks, suggestion or issues.

I wish you happy printing.

09/24/18 Some small improvements made, 1. additional text on the flange of Part B, 2. Better visibility in the OpenScad CSG compiler (fast preview), 3. fix some older little bugs.

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