UVIL: Backlit Blacklight Nightlight (or SteamPunk Indicator Lamp)





Introduction: UVIL: Backlit Blacklight Nightlight (or SteamPunk Indicator Lamp)

How to put together an eerily glowing neo-retropostmodern ultraviolet indicator lamp.

This shows the construction of the first two that I made as a way to evaluate the PCB etching process outlined in another Instructable. My idea is to use these as indicator lamps in some other projects.

My son insisted that I enter it into the LED contest because he wants a TV-B-Gone kit, so be sure to vote it up if you like it. (Click the + icon at the top of this page)

You should open this pre-requisite Instructable in a new tab or window: https://www.instructables.com/id/Stop-using-Ferric-Chloride-etchant!--A-better-etc/

It is the method used to do the etching in this instructable and has the added bonus of giving the PCB's a nice green tint.

Eventually I will make stained wood and brushed aluminum enclosures for these. I also plan to make use of these as indicators on some projects. (They are actually quite significantly brighter than they appear in the pictures)

Step 1: Gather Materials

Aside from the etching materials (which are listed in the separate Instructable noted) you will only need:

  • Ultraviolet LED's - I got 200 for $10 on eBay. I think cool backlight effects could be made with any LED combination you like, my preference just happens to be UV.
  • Fluorescent acrylic - McMaster carries this, as do alot of industrial supply houses. I got mine for $0.99 in the form of a tacky cutting board from a thrift store. Again, green is my preference, but the material comes in a couple of fluorescent colors. I think that maybe I'd like to try red, too.
  • Standoffs - I used #8 threaded couplers

Step 2: Layout the Top Board

You will be etching two boards. One will be the front/top (whatever you want to display) and the other will be the back/bottom, holding the batteries and UV LED's.

You can be pretty free laying out the top, just be sure to stay far enough back from the edges to clear your stand-offs and Remember to reverse your image for etching!

Step 3: Etch the Top Board / Layout the Bottom Board

After etching the top board using the process outlined at https://www.instructables.com/id/Stop-using-Ferric-Chloride-etchant!--A-better-etc/ you will need another board to hold the LED's and batteries. The second board needs to be the same size as the first.

You will need to decide:

1.) How many UV LED's you want to use
2.) Where to place the LED's
3.) How to supply the power to the LED's

I took a little 1-LED coin-cell flashlight and replaced the white LED with a UV LED. This allowed me to shine from behind the board to see what different placements would look like. Bending the LED's over (rather than have them aimed at 90 degrees to the board) gives more coverage.

Once you have decided where to placed the LED's you need to decide where to place the battery (or power wires). You can get PCB-mount coin-cell holders - I cut a piece of battery contact from and old lamp, bent it, and riveted it to the board for one contact. The other contact is just a large pad on the board.

If you wonder why there are so many parallel traces on mine, it is because I wanted to see how well traces of different widths would come out of the etch.

Step 4: Etch & Solder the Bottom Board / Cut Acrylic

After etching the bottom board and fixing the components in place you need to cut out the acrylic to size. Be sure to cut out for your standoffs, too.

This doesn't have to be pretty since it's only purpose is to diffuse and fluoresce in the background. In fact, I scuffed it up with some 100 grit sand paper to help diffusion.

Step 5: Assemble / Gape and Genuflect

All three layers are now done - time to make a big green sandwich. Assembly is straight forward: Top layer on top, acrylic under that, PCB next.

A picture of my first UVIL assembly is below.

Also is a (wiggled, blurry) picture of the Olivian UVIL backside showing the roller limit switch I added so that you can turn it off just by laying it down. I wanted to use a tadly mercury switch but didn't have one on hand. Incidentally, The Olivian UVIL bottom PCB also used a sharpie pen as resist (rather than toner transfer)



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    That was short. I like the simplicity. Great job

    Thanks! And yeah, I believe the whole process, excluding etching, took me about 30 min.

    The first board only took maybe 30 minutes. However, The etchant seemed to dilute quickly and each additional etch took much longer. The last board I etched took more than 12 hours. The longer the etch, the more the toner seemed to suffer. I may attribute some of this to the temperature of my basement, though. I need to try some temperature-controlled tests. I may also attribute some of this to my using 2-oz double-sided blanks, so I need to get some 1/2-ox stock.

    I prefer to use sponge method of etching. Dip soft sponge into etchant and rub board. This process is very fast. Nice job though.

    Years later ... I finally started playing with the sponge method earlier this year. You are quite correct! I also started using the stronger Hydrogen Peroxide that I can get from a beauty supply chain, too. Etching takes under 60 seconds in most cases now and uses about a shot glass of etchant!

    Great Job! 4 years and still a very cool project. Well done!! Have you thought of using a caged ball instead of your roller switch? Looks great now just thought it might add even a little more "punk". Great Job!!!!!!

    Thanks for the kind words! I ended up replacing the limit switch with a mercury switch from an old thermostat.

    Very cool I want one!!  Thanks for all the info also!!

    Way cool! I'm going to make a "call sign" sign for my ham shack... 73, Rusty KC5QNK