<img src="%PUBURLPATH%/RevelationSpace/NewsItem11x02x13x0/board_scaled.jpg" alt="board_scaled.jpg" width='320' style='float: right; padding-left: 0.5em;'/> Tonight we finally got around to testing the UV lighting tables and etching chemicals in the electronics lab. For the [TwinklingBar|twinkling bar] project we need 20 pcb's for the PWM controllers that will each drive 5 RGB led's. After making the design in eaglecad, and printing that on transparant plastic, we went for the first exposure. We did not get it right immediately, as this attempt was underexposed and failed to etch. The second try we got it right. The result is aesthetically pleasing, although due to an honest mistake by someone who shall remain nameless in this article the design was upside down and thus unusable.
The UV lighting tables has two arrays of UV tubes, both the upper and lower side of the PCB to be etched are illuminated by 6 20W fluorescent tubes each. The timer allows to set the exposure length, which we found out to be optimal around 4 minutes. The tables have quite some history. Originally owned by the TH Rijswijk (now Haagse Hogeschool), they came into the possession of the !CabFabLab two years ago. Early 2010 they were donated to !RevSpace.
Some work was needed though. One table had a broken timer, the other a really short tube for the vacuum pump. The electronics were hacked, and there was no safety release for the UV-tubes which led to the possibility of opening up the cover and looking into the 240W of UV blasting at your eyes directly. Mostly thanks to Ikarus, and some earlier work on the timer by gmc, we now have one working table and one for spare parts.
Although sending of your design to Hungary or China is probably easier and cheaper nowadays, the feeling of having made your own PCB is well worth it. By having the necessary installations and chemicals to etch PCB's, you can go from idea to PCB in under an hour at !RevSpace!