Step 1: Stuff You Will Need
- access to a laser cutter
- LED ribbon
- 9 volt battery or 12 volt regulated plug pack
- battery snap
- block of wood to mount the base.
- 3mm cast acrylic sheet, clear or the florescent colours for the sign
- tools, sand paper, timber finish, soldering iron, drill, saw etc
- A flip flop circuit
- fine hook up wire
- A CAD drawing program that can import and export DXF files is also useful
- acrylic glue
- 3mm cast acrylic sheet solid colour for the base
Step 2: Making the Wooden Base (glow in the Dark Sign)
The slot was cut on a bench saw and the waste cut out with a chisel. A 9mm slot 10mm deep was cut on the top side as the ribbon is 9mm wide. 2 pieces of 3mm thick acrylic were cut as spaces to locate and support the sign, and these are fitted on top of the ribbon.
After test fitting everything and soldering the battery snap on the 2 smaller blocks can be glued in. The base was sanded up and given a coat of furniture oil.
Step 3: Making the Laser Cut Base (blinking Sign)
Once the base is glued together the ribbons can have wires soldered to them, the adhesive backing removed and placed in the base.There is some overlap in the middle, as the ribbons are 9 mm wide and the space is only 15mm.
Step 4: Wiring Up the Ribbons
The blinking sign has a flip flop circuit driving the 2 ribbons. Flip flops are a pretty common circuit and there is lots of info on the net about them, you can buy them as a kit or make your own with a few cents worth of parts. there is even an instructable on how to build one here. https://www.instructables.com/id/Flip-flop-LED-circuit/
Just wire in the ribbons where the 2 LEDs would normally go. The kit that I got has pots which allow you to adjust the blink rate.
A word of warning about plug packs there are 2 types, regulated and unregulated. Just because an unregulated plug pack says its output is 12 volts, doesn't mean you will get 12 volts out of it, unless it is connected to the correct load the output could be double that, frying your flip-flop, and LEDs. Go for a regulated plug pack, its output voltage will be more stable regardless of the load.
Step 5: Engraving the Sign
This was removed with Gimp, which is a free, photo editing software Linux, Macs and Windows.
Engraving takes a long time with a laser cutter as the gantry whizzes back and forth across the material not unlike a printer, so the robot took around 1/2 an hour to engrave.
With the text I drew it in pro desktop, and exported it as a dxf file which will be recognized as something to cut by the laser, I then turned the cut speed up, and the power level down, so that the text would only be cut part way through the plastic. This means that the text can be engraved in around 30 seconds.
Some interesting effects can be made by playing with the focus of the laser as well as the power levels, Moving the material closer to the lasers lens gave a ghosting effect, while further away gave a wide line effect.
I also found that the engraving is slightly better when viewed from the back side, so I mirrored the text and the robot.
Step 6: Other Stuff
I am also planing to make a blinking sign with coloured LEDs an clear acrylic, which I think could possibly work better than the coloured plastic, and white LEDs
Come to think of it there is no reason I could have 3, 4 or even more layers to the sign and run it off a micro controller, and have some real animation happening.