This instructable will teach you how to make a device that shoots an unbent paperclip using only a rubber band, a mechanical pencil, and scotch tape. The final product looks like an ordinary mechanical pencil but is far from it. Picture one is the pencil before it is modified, and picture two is after its modification. Can you tell the difference?
-Mechanical pencil (I used a Bic one)
-Leatherman or similar multitool
-Wire cutters (optional)
Attention: Unless your idea of fun is having a sharp paperclip sticking out of a person/animal I highly recommend not shooting this at any thing/one because it will break skin and stick. If you are not careful, this could happen to you too. I am not responsible for anything stupid you do with this.
Step 1: Take Apart the Pencil
First you want to remove the tip from your mechanical pencil. I could just pull mine off with my hands, but you may need your pliers to do this. Some also unscrew. Set the tip aside. Once you have the tip removed, press down on the eraser, like you would to feed more lead through the pencil. Where the tip was, you should see the end move out. Find the narrow tube (green in the picture) and cut it with the multitool. Be careful, pieces will go flying. It should separate into 3 major parts, the inner tube, the outer tube, and the spring. You do not need the spring for this project. Take the inner tube. With your pliers, bend the remaining narrow tube (green part) close to the edge until it breaks. Remove the eraser and let the other part fall out. The inner tube should now be hollow.
Step 2: Re Assembling the Pencil/Barrel
Take your inner tube and a piece of scotch tape. Wrap the tape around the end of the inner tube. Try and fit the inner tube into the outer tube. If it slides easily in and out, you will need to add more tape. If it doesn't go in far enough (like mine did) remove some tape. The goal it to get a really tight fit with the eraser holder the same distance away from the outer tube that it was before you took it apart. It should be hollow all the way through.
Step 3: Modifying the Rubber Band and Paper Clip
Next, bend the paperclip, so that it is straight. You want to make it a straight as possible, so try and get out all the kinks in it. Make sure it slides easily through the barrel (pencil). Then, take your wire cutters and cut the paperclip so that it fits entirely inside the pencil (with the tip and eraser on). When you cut it, it should get sharp. If it doesn't, cut it at an angle. Place the paperclip inside the pencil and put the tip and eraser back on the pencil. Double band the rubber band. Take a piece of scotch tape and wrap it around the rubber band. This protects the rubber band and makes it easier to shoot the paper clip.
Step 4: Shooting and Results
To shoot the device, remove the tip and eraser. Let the paperclip slide partway out of the eraser end. Make sure the end you see is the dull end. Take the opposite side of the rubber band that the tape is on and hold it to the barrel. If your pencil has a pocket clip, slide it in the clip. Place the tape on the end of the paperclip and pull back, making sure the paperclip is coming back too. Aim and let go. The paperclip easily went through two layers of cardboard. I shot it at a book that I am going to turn into turn into an invisible book shelf eventually. It went through the cover and into the first couple pages. Have fun and be careful!