What started out as an art project for randofo on Instructables after being inspired by the rays of sunlight refracting through a glass water bottle, turned into a quest to capture the magical wonder he felt holding a jar of light in a way only a gearhead knows how. Here’s his contemporary take on the traditional gas lantern.

What You’ll Need

  • Glass jar with twist top (big enough to fit an average CFL bulb)
  • CFL bulb
  • Disposable camera
  • AA battery holder
  • Switch
  • Roll of magnet wire

Prepping the Circuit Board

Use a screwdriver to pop open the disposable camera case and access the circuit board inside. Be careful not to touch the capacitor cylinder – it’s charged and can potentially give you a nice jolt.

Jar Lantern - Disassemble Disposable Camera

Once you pull out the circuit board, cut off the capacitor and flash tube. Discharge the capacitor by bridging the leads with a long screwdriver that you don’t mind scarring – and obviously, don’t touch the metal part of the screwdriver while doing this. Alternatively, you can use a resistor and touch the leads to form a closed circuit.

Depending on the size of your jar lid, cut away any parts that stick out from the board like battery terminals and extra wiring and trim off excess plastic where there’s no circuitry.

Jar Lantern - Solder Wires to Circuit Board

Fire up your soldering gun because this is where the magic happens. Pop off the push tab on top of the flash charge switch and solder the switch’s terminals together. Cut 2 pieces magnet wire 3″ each and strip off 1/2″ of insulation from each end. Solder one wire to a ground terminal and the other to the terminal of the inverting transformer that the diode is connected to.

Mounting the Switch

Splice in the switch to the red wire of the battery holder. Drill a small hole in the jar lid and push the switch through it from the underside of the lid and lock it in place with the mounting nut.

Jar Lantern - Cirbuit Board Assembly

Solder the red wire from the switch to where the positive terminal of the battery was connected on the circuit board. Solder the black wire to ground. Hot glue the entire assembly as flush as possible to the inside of the lid. While you want to use a generous amount of glue, be careful not to get it on the threads of the lid or it won’t twist shut properly.

Prepping the CFL Bulb

Use a pair of cutting pliers to punch a small hole in the plastic body where you could stick a screwdriver to pry the base from the glass tube.

Jar Lantern - Prep the CFL Bulb

Unwind the CFL tube’s wires from the posts on the circuit board until the glass portion is free. Scrape the coating off the wires coming out of the CFL bulb with a razor blade, twist the wires together and solder.

Completing the Jar Lantern

Solder the magnet wires coming out of the circuit board to the free leads coming out of the of CFL bulb. Insert a AA battery into the holder inside the lid and test your light. If you soldered everything correctly it should light up when you flip the switch. Twist the lid onto the jar and enjoy the warm light shining through the glass.

Jar Lantern - Complete Assembly

Expect to get 2-6 hours of light depending on the battery and camera circuit board!

For more step-by-step photos and wiring details check out randofo’s Jar Lantern project on Instructables.