If your one of those people who have problems keeping a goldfish alive – I have the perfect solution for you.
This project came about after seeing an image on the web of a goldfish inside a light bulb. I have no idea what I was searching for but the image was striking and I wanted to try and capture something similar.
I figured a real fish would be out of the question so I went on the hunt for some rubber ones. After some searching, I found some on Alibaba Express which were perfect. The next thing I had to do was to find the right type of light bulb. I could have just gutted a real one and used this but they are getting harder to find. The halogen ones I find are harder to mod so I went on the hunt to find something suitable. Luckily I found some on eBay which were exactly what I was looking for.
I’m really happy with the way that this turned out. I was a little worried about how the goldfish would move in the bulb but it turned out great. Adding the LED’s to the bottom was an added bonus as the fish becomes almost florescent in certain colours and it definitely adds something special to the finished result.
NOTE: I have made a whole bunch of these now and have become pretty efficient at putting them together. I have included some extra notes in the 'ible which should help you if you decide to make one.
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Step 1: Watch the Video...
Step 2: Things to Gather
Step 3: Wiring-up the Goldfish
1. Push the wire through the fish. Keep it low on the fish and somewhere near the middle.
2. Once the wire has been pushed through, bend the end again so you make a “U” shape. Then push the end through the fish again. It’s a little hard to explain but I’m sure the images will be self-explanatory
3. Next, and this is an important bit, you need to decide what the turn radius will be for your fish. Too much and he will hit the sides, too little and it will look a bit silly. In the images below you can see that I only left about 10mm and then bent the wire so it was pointing up. This was too small. The ideal length of the wire is around 15mm.
4. Lastly, (and this isn't something I did initially but worked out later) you will need to slightly modify the tail. I found that if you add a little bit of super glue to the side of the fish and stick the tail to it, then it won't touch the sides of the globe. I had to trim down the tail in my initial one (which worked fine as well) but gluing the tail was a lot easier. You add the glue right where the tail joins to the fish and bend the tail slightly so it is touching the glue. Hold in place for 20 seconds and it should be well stuck together.
Step 4: Moding the Battery Holder
This is a pretty simple step but critical if you want it to fit inside the light socket
1. If you try to add the battery holder without moding it, you won't be able to screw the bottom of the socket on. Get your dremel out and remove some of the section shown below.
2. Place inside the socket to see if you can screw the bottom on. Keep on sanding back until it fits.
Step 5: Adding the Motor to the Light Socket
The cool thing about the light socket is it has a built in on/off switch which I utilized. It makes wiring up the battery and motor simple too.
1. Add a wire to the copper "tongue" inside the socket. Bend the tongue up so it is neraly vertical
2. Solder another to one of the small copper hucks inside the socket.
3. Trim the wires and solder on the motor
4. Lastly, add some hot glue to the bottom of the motor (be generous), and glue to the bottom of the socket. Try and get it as straight as possible. You won't be able to add any glue to the sides as the screw section from the globe won't be able to screw in.
Step 6: Attaching the Battery
The important thing to remember here is when wiring-up the battery, you have to make sure you know which way you want the motor to spin. If you get it wrong, then the fish will go backwards. Don't worry if you do (I did!), you can just de-solder and swap around.
1. Attach the battery to the bottom of the light socket with some hot glue
2. Next either solder some wire or even a leg from a resister (which I did for one of the battery holder legs), to each of the battery terminals.
3. Use the screws on the socket to secure the wires to the socket. Test the switch to make sure the motor spins
Step 7: Adding the Goldfish
1. In order for the globe to fit into the socket, you will need to remove the bottom section of the socket. I did it with a dremel
2. The ideal length for the wire is 65mm. This will make sure that the fish sits pretty much in the middle of the globe.
3. Next you need to attach the music wire to the motor shaft. I found the best way to do this was to use a small piece of copper tubing as a sleeve to secure the wire and shaft together. You could also solder it on or glue it. The good thing about using a sleeve is you can remove and adjust the wire if necessary. In the photo above I have used quite a long piece of tube. You only need a small piece around 4mm
4. Test before you screw everything into place.
Step 8: Finishing Touches
Next thing to do is to put the socket together. I had to take off the wire from the motor shaft in order to put it all together.
1. Screw the light bulb into the light socket
2. Screw the battery section onto the socket
4. Lastly, I added some LED lights to the bottom of the globe. I found these lights on eBay and they are great. They can change colour, flash and pulse. They really finish off the project and the really cool thing is, certain colours make the fish glow and look florescent.
5 . Also, as the globe is now top heavy and could easily tumble over if knocked, I decided to glue the bottom of the globe to the LED's. I used some clear epoxy glue to secure to the bottom. You only need a small dab.
Step 9: Finished
I'm really happy with the way this project turned out. The goldfish worked exactly as I had planned when I first thought up this idea. Actually, I was going to have the goldfish stuck with resin inside the globe but I'm glad I went with the motor.
I'm going to make another and have these on my fireplace!
Not too sure how long the battery will last (can't imagine it will be for too long), but considering they are so cheap and easy to replace, it doesn't really matter.
I did think long and hard about how the LED's should be positioned. Initially I wanted to drill a hole in some wood and have them sitting inside this. In the end though I kept it simple and just left them as is.