Purchasing a UV exposure box can be a very costly investment, so instead I made my own. Allowing me to build PCB to a fine detail using an inject printer, this UV exposure box was my last strip-board project. To make sure it is reliable I’ve added a safety cut out switch, LCD menu system and controllable timer to ensure consistent results.
Inspiration for the box came from reading an instructable on www.instructables.com and modifying it for my own needs and desires.
I acquired the UV Leds on eBay for around £6, the tool box itself for £3, the acrylic £5 and everything else was recycled from other projects / skipped items (Such as a bricked netgear router for the power supply).
The UV panel uses 84 leds in a series and parallel configuration, and are 65mm below the acrylic self. This allows to hit the PCB at a uniform level.
The micro controller uses a Finite-State-Machine(FSM) to control its operating logic, with Init, stopped, running, paused and finished states with corresponding LCD readouts.