Sunday, 13 July 2014

UV exposure unit ready for fitting

About six weeks or so ago we pulled apart some UV acrylic nail art lamps with a view to creating an exposure unit for fixing images onto silkscreens (and for fixing solder mask to etched pcbs).

The project stalled for a while due to a number of things, but having recently got the laser cutter working, and successfully getting the CNC router to move about (albeit not exactly drawing shapes yet) we've been inspired to spend a bit more time kitting the unit out with stuff that "just works" so it's on hand, ready to be used, as the need arises.

With this in mind, we spent some time last night getting the UV exposure unit finished - well, the electrics for it, anyway

The controls are all wired up and at the minute we're running the whole thing straight off the mains. All that remains now is to line the bottom of the tray with reflective foil (to hopefully reduce any chance of "striping" as the unit won't actually sit very low down on the underside of the desktop). Once it's installed in our large desk we'll put a relay switch inline with the power supply, so we can control the exposure time using a homebrew digital timer (of course, made from a PIC and a max7219 and some 7 segment LEDs!)

Just to make sure nothing had got damaged during the rewiring, we powered it up to see that it all still worked. Amazingly, it did.

It was only afterwards we realised that had it gone horribly wrong, none of us actually knew were the fuse box is, in the Boiler Room Studios - we could have been left in the pitch dark, feeling pretty stupid. Thankfully it just worked; but we'll make sure we know where the fuses are before we do anything else with mains wiring - just in case......