The Swiffer WetJet is an inexpensive ($20-$25) disposable mop manufactured by Procter and Gamble. It has a receptacle on the back for a tank of cleaning fluid, and a battery-powered pump (actuated by a switch in the handle) that squirts fluid from two nozzles at the front of the mop pad. The entire unit can be disassembled easily, and you can recover the entire pump assembly to use in your own homebrew robotic micropipettor, DNA synthesizer, or bar-bot.
You will need:
* A kitchen knife or utility knife
* Needlenose pliers
* Regular pliers
* A small Phillips head screwdriver
Step 1: Remove the handle
The mop is much easier to work on with the handle off. Conveniently, the handle is secured to the pump assembly and head by nothing more than a spring-loaded button. It's fairly stiff; you may need to push it in with the tip of your Phillips head screwdriver. Depress it enough to twist the handle so that it stays down, then pull the handle off.
A pair of wires runs up the inside of the handle to the switch. If you want to recover all the wiring in one piece, remove the screws from the handgrip (don't forget the angled one at the back) and pry up the lighter-colored pushbutton; the handgrip will come apart and you can slide the entire aluminum handle off over the 10A SPST switch inside. You can also just cut the wires.
Step 2: Remove the rest of the handle
Slide up the battery cover and open the battery case. Unscrew the two Phillips head screws and set them aside. Push down the light purple plunger/button at the top of the battery case, and the battery case will disengage from the rest of the mop head. Twist and pull on the aluminum handle to remove the handle and battery case from the socket at the top of the mop head.