Bic Multi-Purpose Disassembly

Some time ago, a lighter in my house ran out of fuel and I decided to take it apart despite “common sense” (i.e. a blind and baseless fear of fire) telling me not to. To be fair, the last time I took apart a lighter, there were hair-singeing consequences, but this time, I verified that the lighter was completely empty of fuel to avoid this risk.

The lighter is disassembled by removing a single screw towards the back, a press-fit collar towards the front, and prying the two halves of the glued-together case apart. Inside, there are two levers: a metallic main lever pushed directly by the trigger operates the piezoelectric igniter while a secondary plastic one pushes the gas valve on the cartridge. A torsion spring holds the two levers back, preventing a gas leak, while a compression spring pushes down on the torsion spring, ensuring it stays in the proper position. The piezoelectric lighter is pushed by a locking block containing a zigzag-shaped slot that engages a small projection on the safety button. This slot stops the main lever from moving beyond a certain position unless the safety button is pressed down, disengaging the projection. However, the main lever can still move enough to start the flow of gas without the safety button being pressed.

(see featured image for all components installed)

The lighter gas is stored in the same cartridge as the classic Bic cigarette lighters, as noted by many people online. A rubber fitting and thin plastic tube connect the cartridge’s gas nozzle to the nozzle at the lighter’s tip. The lighter “stick” is a steel tube that contains a plastic bracket to hold the gas tube and ignition wire. Tube and wire run parallel through this bracket, and at the top, the stripped wire end is held against the metallic nozzle to make a somewhat secure electrical connection. Then, a plastic cap holds the two halves of the bracket together at the tip while allowing the nozzle to protrude. When the trigger is pressed, gas flows out of the nozzle while the piezoelectric igniter causes a spark to jump from the nozzle to a triangular projection stamped out of the tube, something you have no doubt observed.

I removed the gas cartridge from the lighter and sawed off the very top of the stick to expose the nozzle. I plan to use it as a blowtorch igniter to replace the empty cigarette lighter I am currently using when its ferrocerium “flint” is used up.