recently i built a custom case that consist of multiple stackable sub cases:
https://modwiggler.com/forum/viewtopic.php?p=3993355#p3993355

first i tried to use 8mm x 80mm metal bolts between the cases but i was not successful.
I was hoping to be able to stack & unstack the cases without the need for any tool.

after i realised that its totally ok for me using a tool in favour of a good connection between the cases i finally mounted a 3mm metal plate with 2 M5 holes on top of each sub case
it looks like a strong connection with nothing to worry about.

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