This is a full size 3d printed Pop'n Music controller. It's a bit silly in construction (laser cut acrylic is more sensible), but works
...Show more well.
BOM:
1.5kg of PETG or PLA
atmega32u4 breakout board or similar for USBemani
5V regulator (optional)
9x Samduck 100mm buttons from makestick
2x Sanwa 24mm snap-in buttons from makestick
9x arcade LEDs from ebay
18x 0.250in crimp connectors
22x 0.187in crimp connectors
64x M3x10mm screws
64x M3 nuts
22x M3x4mm screws
22x M3x3.8 heat-set inserts
4x M2.5x5 screws
~50 feet of wire
PS2 extension cable