Introduction: Telegraph Pendant
So far, I haven't really been sold on the need for wearable tech. Maybe I'm just getting old, but the only wearable tech I have is an 80's calculator watch. Getting to the calculator on my phone is just too much trouble. I need my calculator ready at all times.
Like the calculator watch, I was inspired by seemingly (or actually) useless wearable tech and decided the next piece of wearable tech I needed was a telegraph pendant to make those cross-office memos just a bit easier.
Now, I know telegraphs typically use a wire to send their messages, but everything is wireless these days, so I thought an LED would do just fine to visually transmit messages.
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Step 1: Materials and Tools
24g or similar wire
needle nose pliers and wire clippers
access to a laser cutter
quick dry tacky glue
one LED (I salvaged mine from a finger light)
CR2032 button cell battery
The following items are not hard to come by, but are not standard, and may therefore, require small adjustments to assembly or the laser cut design. For example, I tore apart several click pens to find a spring I liked. There wasn't a single spring alike in any of the pens I opened. Therefore, you may need to spend some time finding items that fit the cut design or you could adjust the holes in the cut design to fit what you find.
click pen (to salvage a small spring)
two small screws .1" diameter threads
two strong magnets .4"
small metal peg (I think the one I used was part of a travel chess set. Anything small and conductive will work, so even some low gauge wire should do the trick.)
All the metal items in this list need to be conductive. So, before starting, use your battery and led to test all the metal items. Remember that the long end of the led is the positive end. If you put it on the battery the wrong way, it will burn out the led.
Step 2: Cut and Color Pieces
I've attached the cut files below. They're slightly different than the ones pictured since I had to make some adjustments from my original cut to make it fit together better.
Color the visible sides of the pieces with a marker or watercolor as shown, or color both sides of all pieces to make things simpler.
Step 3: Base Plate
Thread a 5" piece of conductive thread through the smaller hole in the base plate, and use a small screw (.1" diameter threads) to hold it in place with the majority of the length on the bottom.
Trim off the excess threat on the top.
Glue one of the magnet holder pieces on top of the bottom of the base plate with the thread sticking out the end as shown. I use Aleene's Quick Dry Tacky Glue when gluing wood. It's my favorite multipurpose glue.
Step 4: Back Plate
Glue the other magnet holder piece onto the back plate as shown.
Note: There should be a hole where I have a screwdriver indention. The screw I used was longer than anticipated in my original design, so I added a hole to the cut file for easier assembly.
Super glue the magnets into the holes in both sides of the plates making sure to glue them in the proper direction. You want them to attract, not repel each other.
Step 5: Begin Pivot Point
Cut a 3" piece of 24g wire and twist the end tightly in a small spiral.
Thread the wire into one of the larger arched pieces so that the wire fits into the indention.
Glue it in place by attaching one of the smaller arched pieces, and placing it in to the base plate to ensure it dries properly aligned.
Do NOT glue into the base plate yet.
Step 6: Lever
Cut a 6" piece of conductive thread, and put one end through the hole in the lever that matches the peg.
Put the peg in the hole to hold it in place.
Super glue the peg in place.
Stretch the thread tightly across the side with the indention in it, and hold the other end in place with the spring you salvaged from a click pen.
Glue the thread in place, and stack the matching piece on top with the indentions pressed together as shown.
Do NOT glue the spring in place yet. It is only there at this point to make sure the pieces are glued together properly aligned.
Thread the wire from the previous step into the indentions in the lever and then through the other larger arched piece. Cut off the excess wire with just enough to twist up the end inside the indention in the arched piece.
Glue the smaller arched piece over the end and place the whole assembly into the base plate to ensure it dries properly aligned.
Glue the whole assembly into the base plate.
Step 7: Spring
Twist a small screw into the end of the spring. It should fit tightly without stretching it out and still fit easily into the hole in the lever. The top of the screw will prevent it from falling through.
Cut a .5" piece of wire and bend it slightly.
Hold the spring in place under the base plate so that the peg is slightly above the screw below it.
Test the lever and spring placement by pressing on the peg end.
Once the tension feels right, put the piece of wire in the spring just below the base plate and super glue it in place. Cut off the excess spring about .25" away from the base plate. You'll need to attach your LED to this spring later.
Step 8: Glue on the Sides
I originally only put on the two long sides, but you should glue on all four sides.
The back will only be attached by the magnet, so don't put glue on the back plate, but DO put it in place while the sides are drying to ensure they dry in the proper alignment.
Use some rubber bands to make sure it glues tightly.
Step 9: Battery Pack
To keep the battery from touching only what you want it to, you'll need a battery pack. I used a piece binding, but any small piece of fabric will do.
Stitch a spiral in one end using the conductive thread. Leave a few inches hanging off.
Wrap the fabric around the battery tightly. I wrapped mine a couple times and struggled to fit it into the base, so I recommend only wrapping it so the ends overlap once.
Stitch up one end with regular thread and leave the conductive thread sticking out this end.
Put the battery in the sleeve, making sure that the negative side is touching the conductive thread spiral, and cut off the excess fabric on the end.
Mark the side of the pack that doesn't have the conductive thread on it as the positive side.
Put one stitch in the center of the open end to hold the battery in.
This makes it easy enough to cut the battery out and replace it when needed.
Note: There are some cuts in the fabric I made for attaching the led that didn't work out. Ignore them.
Step 10: Installing Battery Pack
Tie the excess conductive thread from the battery pack to the excess thread on the bottom of the base plate. Cut off the excess.
Put the LED into the hole in the end and bend the negative side of the led around the spring.
With the open end of the battery pack facing the LED and the positive side face-up, slide it into the space next the the LED with the positive arm of the LED inside the positive side of the battery pack.
Place the back on and start sending messages!
Step 11: Enjoy!
Second Prize in the