Intro: The Time Machine || an Awesome Clock Hack
The time machine used to be considered science fiction..... But not anymore! I have found a way to hack a normal mechanical clock to fast forward and reverse time! Well, kind of. In this instructable, I will show you how to hack a clock to run up to 60x faster. This hack will also let you run the clock in reverse. It can be modified with only a few cheap parts. The video below will show what this "time machine" can do as well as how I built it.
Lets get started!
Step 1: How It Works
My clock hack works by utilizing the existing drive coil and gear train inside the clock. The clock has a "U" shaped electromagnet inside that surrounds a small permanent ring magnet. This ring magnet is glued inside a gear. The original clock works by switching the direction of current flowing through the electromagnet once per second. When the current flows one way, the two sides of the electromagnet are polarized differently, this causes the ring magnet to rotate one half revolution until the poles on the magnet line up with their opposing counterparts on the electromagnet. When the current flows the opposite direction, the polarities of the electromagnet to change, therefore making the ring magnet gear rotate another half revolution. This can be better explained by the picture above. In a normal clock, the electromagnet reverses direction every second, but in my hacked version, it reverses current many times per second. This is achieved using a 555 timer circuit.
A 555 timer is a IC that puts out a different frequency PWM signal based on the resistor and capacitor values between ground, pins 2 and 6, and the output of pin 3. Having a large capacitor and a large resistor makes a very low frequency. By decreasing the resistor value, the frequency increases. A PWM signal consists of a time when pin 3 is grounded, and when pin 3 is tied to VCC. The amount of time it takes to go through one cycle(on/off) is the frequency. When pin 3 is grounded, or off, current flows through the clock coil from the power rail, through the coil and 100 ohm resistor, and to the grounded pin 3. When pin 3 is high, current flows the opposite direction, from the 555 timer, through the coil and resistor, and to ground. This is basically how my time machine circuit works.
Now that you know the "why" of how my time machine clock hack works, I will show you how to actually build it.
Step 2: Tools
For this project, you will only need a few simple tools.
You will need:
- A soldering iron
- A 6V power supply
- Wire cutters
- A screwdriver
- Wire strippers
Step 3: Materials
This project only requires a few cheap materials:
- An electro-mechanical wall or decoration clock.(Usually any clock that takes 1 AA battery)
- 555 timer
- 100k potentiometer
- 1uF capacitor
- 2x 100 ohm resistors
- 8 pin DIP socket
Step 4: Disassembling the Clock
The first step of building the time machine is to disassemble the clock. First, use a screwdriver to lift the plastic tabs on the side of the plastic back. You should then be able to pop off the back, revealing the gears, electromagnet, and circuit board. You can then remove all the gears. These should be easily to remove because they were only held in place by the plastic back. After this, remove the electromagnet and circuit board. This takes a little bit of patience, but you can wiggle it out. Once the coil and board are removed, its time to go to the next step.
Step 5: Preparing the Coil
The clock coil is glued to the circuit board, which has holes that let it mount to the clock, so we don't want to remove this. Instead, we will just electrically disconnect the coil from the board. To do this, use a sharp screwdriver to scratch the copper traces between the black microprocessor and the coil connection points on the board. There should now be no electrical connection between the old control circuit and the electromagnetic coil. Now, the coil in the clock will need to be externally wired to the new circuit board. Just solder wires to the two solder points on the board. The clock coil should now be ready.
Step 6: Soldering the Circuit Board
The circuit board is what holds all the electrical components of the time machine. To build it, use the circuit diagram to solder components to the perfboard. Then, connect the electrical components using solder and small wire. You can duplicate my circuit as shown in the pictures above. Finally, connect the coil and power wires to the control board.
Step 7: Replacing the Components
After everything is done with the electronics, it is time to replace the coil and gears in the clock. This is relatively easy, just put back everything in the place where you found it. To let the coil wire out, cut a chunk out of the plastic back. You can then replace the plastic back. There you go! Your "Time Machine" is now ready to go.
Step 8: It Works!
To test the "Time Machine", hook it up to a power supply of 6V, and adjust the potentiometer until the second hand starts to spin. It should go super fast, about 1 revolution per second. This is about 60 times faster than the old clock circuit. to make the clock go in reverse, fiddle with the potentiometer until it does. This "Time Machine" can be used as a decoration, a cool sci fi toy, or as a way to make a cool video. I used it to make a video where time was slowed down everywhere but near the clock.
Good luck building and make sure to vote for me in the Sci Fi and Trash to Treasure contests!
Thanks for reading!