I’ve always wanted to etch PCBs at home. For several years I’ve been acquiring the necessary equipment to do so. I tried doing some boards using the iron-on transfer method with limited success. I started to think about ways to build a UV box to do the UV film method.
While looking around on Craigslist to see if I could find a box that would fit the bill, I happened across this one: an old file box with drawer and an interlock to keep the drawer closed. The seller only wanted $5 for it. She asked when I picked it up what I was planning to do with it, and I tried to explain, but I don’t think she really understood.
I started working on it the next day. The first thing I did was remove the divider inside by breaking the spot welds with a cold chisel. I then pop-riveted some aluminum angle inside so I had a place to lay in some black acrylic which would be the shelf to hold the UV arrays. I found a perf board design that was perfect for making a large LED array. In total, there are 880 UV LED’s and 440 resistors.
I used a bathroom fan timer to control the exposure time, installed an interlock switch so if the lid gets opened while power is on, it kills all power.
I’ve etched quite a few boards so far with it, and it works perfectly.