That's a kind of project that took a long time to be finished, despite its simplicity! That's because I have used, for a long time, a UV fluorescent lamp box to do my printed circuit boards and I always thought that another one, using UV LED's, could wait once more time to be assembled!... Until now!
The main design consists of a wood-covered MDF box, a UV LED matrix board and a PIC microcontroller to control exposure time. All the projecs is described and available below.

Supplies

* Laser-cut MDF parts;

* light imbuia sheet;

* UV LED array;

* PIC microcontroller timer circuit.

Step 1: Electronics

I developed a PIC and C 16F628A code-based timer circuit that controls a set of UV LEDs for the user-defined time. When the time is up, the LED array is turned off and beeps.
The circuit and code can be seen in the attached files.

Step 2: Assembly

Assembly is easy and can be seen in the following images. Simply glue the laser-cut MDF pieces and then cover the box with a sheet of wood, finished with 2 layers of varnish.
After that, the electronics are assembled, as shown in the pictures... Files attached!

Timer.dwg
Download

Step 3: The Final Result

Tests show that the project works very well, improving PCB constructions. UV LEDs are better than UV lamps, resulting in high quality PCBs.
I hope you enjoy this project!