A maker called Uncle Stem built a 7x scale replica of a 16x2 LCD using over 1,000 addressable LEDs across custom PCBs, and it is fully compatible with the LiquidCrystal_I2C library.
The build rejects shortcuts at every layer. Each character sits on its own PCB, soldered using a 3D-printed paste stencil. Nickel strip, the same material used in Li-ion battery packs, connects the boards. An RP2040 handles the I2C interface and stores the original HD44780 character set, so any existing Arduino sketch drives it without modification. The green substrate is laser-cut plywood, acrylic and office paper form the diffuser, and 7:1 scale pin headers are machined from brass rod.
The engineering decisions buried in the middle of this build are what make the full video worth watching: the stencil fabrication workflow, the nickel strip interconnect strategy, and the RP2040 firmware approach that clones a 40-year-old parallel interface over I2C are all reusable techniques with applications well beyond novelty scale projects.
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