Step 5: Putting the Cover On and Finishing it Up
Next, take that third TP roll and bend it so it fits over the blade. Make sure the tube doesn't obstruct the blade's movement, but that it's close enough that the blade won't pop off from the rubber bands.
You may see in the pictures below that I didn't use a TP tube. This is because I didn't read the instructions fully and I didn't take more than two tubes from home (my college doesn't have tube TP, it's all paper core). That being said, the cardboard from a 12 pack of pop will work fine if you cut it to the size of a TP tube.
Use your handy duct tape and secure it. Cut a bit out of the bottom of the the 3rd tube so you can clamp the blade to the bottom tubes. Now take out the bottom fastener that held the blade in place and use the paper clamp to hold it there now.
Now you have a hidden blade!
The only thing to do now is secure it to your arm. Get a strip of duct tape, sticky side up, and tape from the inside of the device over your arm to the other side. Place another piece of tape on top to keep it from sticking to your arm/clothes.