We begin this journey with a really inexpensive mechanical pencil.Pencil:
If the pencil isn't working correctly or the eraser is missing then you can feel better about what you're doing. You won't be tossing a broken pencil into the trash where it will eventually end up in a landfill! Anything you can do to preserve your environment is a step in the right direction.
Okay, the next step is to break the pencil down into its component parts. First, remove the eraser from the pencil. This will allow you to remove all of the graphite and save it for other uses. Those other uses would include refilling another mechanical pencil! Remember, save the environment!
Ripping the plunger part of the pencil out requires a decent amount of force. Be careful, if you bruise your hands or otherwise injure yourself, it'll hurt. Unless you're a masochist, pain's generally a bad thing. There should be a little spring left inside the body of the pencil or stuck to the end of the plunger. You will need this spring later so make sure you keep track of it.
Now, if the little black lead feeder thing wasn't damaged, you will need to bend the two halves of this back towards the shaft. If this part was broken off when you removed the plunger, you will need to follow the next step. Either way, your projectile launcher might make a little rattling noise due to a little cylinder thing left behind in the cap. If you would like to rid yourself from this annoyance, or deal with the broken feeder mentioned above, then you will need to remove the cap. This will require yet another exertion of force. Be careful. It really doesn't matter what you do with the cylinder or the cap. However, I would recommend replacing the cap for aesthetic reasons. If your lead feeder was broken, you want to take the pieces from it and save them for later.
The next step is to carefully break the plunger in half. This pencil has convenient holes on its plunger where it should be broken; what luck!This is what you should have at this point:
Now, take the top half of the plunger that used to contain the eraser and stuff the eraser back into it. Set this piece aside, it will serve as our projectile later. If you didn't have an eraser, the projectile launcher will still work but you will have a slightly more dangerous variant.
Take the other half of the plunger and forcefully push one of the ends of the spring into the opening at the top. You do not want to waste too much of the spring so don't push too much of it in. If your lead feeder was broken, you want to use the pieces between the body and tube when following the next step. Now, you want to cram this back into the body of the pencil with the spring facing out. The black lead feeder thing should add enough extra width to keep the bottom half of the plunger from ever coming back out.What you should have now:
At this point, your mechanical pencil projectile launcher is complete. Looks a lot like the original pencil, eh? Simply take the plunger with the eraser, place it into the body of the pencil, push down with your thumb, and then slide your finger away. The end will fly out and travel a distance of around 10 feet. Cool right? Absolutely. You'll never feel the same about office supplies again. Oh yeah, if you're looking for a little more power, two of those springs stuck together will give you added distance.