I’m the type of person that misplaces everything, keys, pocket knives, wallets, glasses, cell phones; nothing is safe once I’ve laid my hands on it. After losing my keys for the millionth time I decided I needed to do something about it. For a while I tried one of those gadgets that beeps loudly when you whistle allowing you to home in on the location of your keys, the problem with that was that it would go off at any loud noise and after it decided to go off several times during class I decided it was time to find a better solution. What I came up with was a simple yet effective glow in the dark fob. Now I know what some of you are thinking, “What use is a glow in the dark fob when I’m trying to find my key’s during the day?” and the simple answer is that it isn’t very much use at all, but there have been many times when I misplaced something during the day, searched for it without any luck, and found it by the bright glow of the fob once it got dark.
So for those of you out there who share my inability to keep track of things please feel free to read on and learn how to make a glow in the dark fob that is both functional and stylish.
Step 1: Materials & Tools
20 minute epoxy: You need at least 20 minutes of working time, instant and 5 minute epoxy sets up way to fast.
Glow Powder: There are many colors to choose from, however, I suggest V10 Green it glows the brightest and longest. Glow powder can be purchased on Amazon or Ebay, I bought a ½ ounce for around 8 dollars.
¼” outside diameter flexible clear plastic tubing: can be purchase very inexpensively at any hardware store. 1 foot of tubing should be more than enough.
Metal or plastic tubing that will snuggly fit the outside diameter of the rubber tubing. (I used an aluminum arrow that I got for free from the local archery shop).
Spring rings (key rings): you probably have some lying around the house.
Pipe cutter (can be purchased an any home improvement store for under 5 dollars).
Xacto knife or other sharp blade.
6ml syringe (can be purchased for under a dollar at tractor supply).
Sand paper (220 grit would be fine). The blue pencil length tool in the picture is my sand paper, it's called a sanding stick and can be purchased from jewelry supply companies like Rio Grande.
Jeweler’s files (not necessary but helpful).
Power drill and 3/32” or 1/8” drill bit.
Power sander (not necessary but helpful).
Something to thoroughly mix epoxy with, (I use an old sculpting tool, but a tooth pick or popsicle stick would work fine).
Wax paper or small disposable container to mix epoxy in.
Step 2: Cutting the Rubber Tubing.
Start off by cutting your clear plastic tubing into 1” to 2” sections depending on how long you want to make your glow fob. I cut several pieces so that I could make more than one glow fob and so that I didn't have to waste any extra epoxy or glow powder.
Step 3: Mixing the Glow Powder and Epoxy
Before you begin mixing make sure that you have your syringe, mixing tool, glow powder and cut pieces of plastic tubing handy so you don’t have to frantically search for them in the minutes to come. Start by putting a dime sized glob of the epoxy compounds down in your mixing bowl or on the wax paper. Right beside the epoxy place a pile of glow powder, as for measurements, I used roughly a 60/40 mixture, 60% epoxy and 40% glow powder by volume. This is by no means an exact measurement, I just eyeballed it and did a few tests with different amounts and found this to be the best combination for me.
With the epoxy and glow powder ready, start mixing the epoxy while slowly incorporating the glow powder. Keep mixing until you have added all of the glow powder and the epoxy appears to be thoroughly combined. Remember that the more you mix the faster the epoxy will set up, so don’t go nuts, mix just enough to combine everything evenly.
Step 4: Getting the Mixture in the Plastic Tube.
At this point the glow pellet part of your fob is basically complete. The last thing I did with mine was to slide them into the metal tubing so that the mixture would dry straight instead of following the curve that some of the pieces of plastic tubing had. Allow your epoxy and glow powder mixture at least an hour to set up and remember to read the epoxy packaging to find information about proper set up and cure times.
Step 5: Making the Casing
For my casing I started with a 2217 aluminum arrow (the numbers relate to the dimensions and wall thickness of the arrow but all I cared about was that the plastic tubing fit perfectly inside the aluminum tubing of the arrow). I got the arrow for free from a local archery shop; it was bent in one section and was no good for shooting but worked well for my purpose.
Using the pipe cutter I cut the aluminum arrow tubing to my desired lengths, usually making the tubing about ¼” longer than the glow pellet I planned on using; i.e. 1” glow pellet = 1 ¼” aluminum tubing, (this allows room for drilling holes to attach spring rings later on). To use the pipe cutter start by turning out the set screw until the pipe can slide between the wheels on one side and the cutting disk on the other. Then tighten the set screw until the cutting wheel just makes contact with the tubing. Make about 2 rotations of the tubing and then tighten the set screw by a quarter turn and make another 2 rotations. Keep doing this until the pipe is cut, this will result in a nice even cut with little clean up. NOTE: what you don’t want to do is crank down on the pipe cutter like you’re the world’s strongest man and try to cut the pipe in one rotation, that’s not how the tool is designed to work and all you’re going to accomplish is ruining a piece of tubing.
Now that your tubing is cut it’s time to make the windows so you can see your glow pellet. I did this by holding the tubing against the top drum of my belt sander which created a very nice clean oval window. If you plan on using this method remember to have a bowl of water close by so that you can quench the tubing when it gets hot from the friction of the sanding belt. If you don’t have a belt sander at home you can make your windows by clamping your tubing in a vise and using different types of files to create different window shapes.
Once your window(s) is/are finished it’s time to drill holes for connecting the fob to a spring ring. Starting about 1/8” down from the top of the fob, mark and drill a hole straight through one side of the tubing and out the other. Note: drilling tubing can be tricky, to help you get started, use a small round or triangle file to create a groove for the tip of the drill bit to set in. After drilling your holes in the top, use some sand paper or a jeweler's file to lightly rough up the inside of the bottom of the tube. This will help hold the glow pellet in place once we start putting things together.
Step 6: Putting It All Together
A dry/cured glow powder and epoxy pellet
A metal tube to contain the pellet (with a variety of interesting windows)
A spring ring
Start by opening the spring ring and threading it through the two holes on the top of the metal tube. With the spring ring in place, insert the glow pellet through the bottom of the tube. Note: if you’re having a hard time getting the pellet into the tubing you can put a small drop of dish soap on the outside of the pellet, this will help it to easily slide into place. If the pellet is a bit too long give it a trim with your Xacto knife. Lastly to hold everything in place we are going to mix up a small batch of epoxy, no glow powder this time. Mix up the epoxy and smear it into any remaining space inside the bottom of the metal tubing (this is why we roughed up the walls in the previous step, so that the epoxy would have something to adhere to. Finally set your completed glow fob on end for an hour to allow the epoxy to dry and you are done.
Step 7: Done
(In case you were wondering I put two black O-rings on the bottom of the glow fob just to change things up.)
Thank you for checking out my first ever Instructable, I hope you found the information within useful and interesting.