should use foil blocks/circles, with the moon shape outlines cut into them to show the phase 

and maybe the day of the week as well 

the foil blocks the light, the negative space (bare fr4) 

block could be squiggly/curved for metal block, or some weird 3d/dither stuff

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cool panels

https://www.reddit.com/r/synthdiy/comments/hy8jg5/some_photos_of_my_in_progress_fully_custom/

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No text 
Rhythm a and b changes to shapes, or I and II

Ins and outs arrows or pulse in out symbols

Inspired by double knot 

Maybe do double knot ish design
Or kandinsky esquej

Could do custom screw nutsa
Maybe yellow or a nice complementary color

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