INSTRUCTABLES PRANK BOX | JAMECO PART NO. 2169504

The Prank Box is basically a sealed wooden box with an electric bell inside that is activated by a tempting push button switch, or a key switch if have one. Once it is turned on, a relay inside the box is latched and it cannot be turned off without knowing the secret trick (spoiler alert: magnets). Quite understandably, a completely sealed box with a ringing bell inside that doesn't seem to stop can quickly become maddening. It is very funny to watch people ponder the implications of the device, reluctantly turn it on, and then stress out when they cannot turn it off. It is even funnier to get panicked emails from your friend in Canada after you mail it to him without any explanation, and he decides to ignore the directions on the box and turn it on. Experience Level: Beginner | Time Required: 5-8 hours

Required tools and parts: Wood glue & woodworking tools Heat gun Paintbrushes Epoxy Electric bell Drill and 1/8” drill bit Red and black wire Clamps Soldering iron

Bill of Materials:

Quantity Jameco SKU Component Name

1 617545 Magnetic Proximity Reed Switch 1 28063* Momentary push button switch 1 105794 Metal 9V Battery Holder 1 216452 9V Battery Snap 1 216401 4-D Battery Holder 1 2077386 PC Mount Relay 1 419186 Heat Shrink Tubing 1 198731 9V Alkaline Battery 4 215845 D-Cell Alkaline Battery 8 182685 Cable Ties

*If you use a keyswitch, be sure it is SPDT type and should have 3 pins (C, NO, NC).

Step 1 – Review Parts and Download Templates Take a moment to be sure you have all the required parts. You can download the two template files titled "DoNotBox.cdr" and "DoNotBox.eps" here: http://www.instructables.com/id/Prank-Box/

Step 2 – Insert Lock Insert the lock into the hole in the front panel from front to back and then epoxy it firmly in place.

Step 3: Mark Mounting Holes for Components Place the wooden mounting bracket atop the bottom side of the box and place all of the components atop their designated spots on the bracket. The reed switch does not have a designated spot, but it should line up flush with the edge of the bracket on the side nearest the 9V battery holder.

Step 4: Glue the Inner-Side of the Box Bottom The bracket should be placed on top and line up to the edge of the box, so when the box is put together the reed switch is flush against the wall of the box. Clamp in place and wait for it to dry.

Step 5: Drill Mounting Holes

Drill the mounting holes with a 1/8" drill bit. It should go deep into the wood, but not pass all the way through.

Step 6: Mount Components Lay two zip ties vertically across the battery holder's footprint and another two horizontally and mount all of the major components to the bracket with screws.

Step 7: Wire It Up Attach the red wire to the common connections for the reed switch and the key switch. Then attach another red wire to the normally open (NO) connections on both switches. Connect these two wires to the red wire from the 9V battery clip. Attach black wires to the two normally closed (NC) connections on both switches. Connect these two wires to the black wire from the 9V battery clip. What you have just done is create a situation in which ground is always connected in the circuit. By engaging one of the switches, you are introducing a positive voltage. This flips the polarity one way or another and latches the relay open or closed. Now when you turn the key, it latches it closed and keeps the bell ringing. When you engage the reed switch, it flips the polarity and latches it open and turns off the bell. You will need to wire the bell to the D battery holder and the relay. First, wire together the black wire from the battery holder to the frame of the bell. Then connect the red wire from the battery holder to the center pin on the

relay. Last, connect the red wire from the battery holder to the coil connection on the bell. This is the mounting terminal not connected to the frame. Cover all the exposed electrical connections with shrink tubing.

Step 8: Heat Shrink Electrical Connections

Step 9: Insert Batteries Insert D batteries in the battery holder and using four more zip ties, firmly band all of the batteries in place both vertically and horizontally.

Step 10: Glue Relay Plug in the 9V battery and epoxy the battery holder in place. Hot glue the relay to the mounting bracket in the free space next to the battery.

Step 11: Bundle Everything Together with Zip Ties If possible, zip tie this bundle to the battery pack to prevent it from interfering with the bell.

Step 12: Glue it together Test to make sure the bell turns on and off. Seal the box shut and apply wood glue to all of the joints and firmly clamp it together.

Step 13: Use a Belt Sander to Round the Edges

Step 14: Make a Sign Laser cut the sign using the template from Step 2. If you don't have a laser cutter, you can use a service like Ponoko, or do this the old-fashioned way with saws, stencils and Exacto blades.

Step 15: Sand and Stain (Optional) Sand the box and wipe it clean. You can put on a coat of stain in a singular direction. When it has dried, lightly sand again and apply the stain in the opposite direction. Lightly sand once more and lay one last coat of stain in the initial direction.

Step 16: Affix the Sign

Step 17: Project Complete It is simply good to distance yourself from the person who engages the box. Remember to be a good southern neighbor and eventually tell them how to turn it off. However, I think 20 - 30 minutes is about a fair amount of time to wait before telling them about the magnet triggered reed switch on the side of the box. Also, when triggering the reed switch, make sure the key is not inserted in the lock and turned. If it is, this will not work.