This design of this lamp shade is oriented on a "classic" vase shape and has some thread decor in addition.
The opening for the socket is 44mm in diameter.
This is the one I used: Amazon.com/Amazon.de/Amazon.co.uk
This is the lightbulp I used: https://amzn.to/2WcWrYW
Because the threads have some quite steep overhangs I increased the extrusion width to 150% nozzle diameter which worked really well.
But because of the steep angles there are repeating little gaps between some layers giving some nice net/grid effect which also increases the amount of light which leaves the lampshade.
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