Compass
Always getting lost? Build this compass out of a CD and a small magnet.
Downloads
Parts Layout
a compact disc (hopefully used / useless)
a small magnet
the outer case of a 50 pack of cd's. (can substitute anything that will hold water and a floating cd, a cd-case looks nice)
some hot glue
some water
a small magnet
the outer case of a 50 pack of cd's. (can substitute anything that will hold water and a floating cd, a cd-case looks nice)
some hot glue
some water
Glue Magnet to CD
Glue the magnet pretty much anywhere on the cd*, with a pole facing radially outwards. If the magnet's pole does not face radially outward the compass will be decieving.
To find the poles, place the magnet in the presence of other magnetic objects. The magnets will attach to each other along their poles if they have enough mechanical freedom to.
To find the poles, place the magnet in the presence of other magnetic objects. The magnets will attach to each other along their poles if they have enough mechanical freedom to.
- Depending on magnet size, glue-ing too far away from the cd's center will tip the cd (think center of mass). But, if the magnet is too close to the center the torque arm length about the center will not allow for the compass to spin / function properly.
Find North
lay the cd+magnet into a bowl of water and watch is align itself with north. The attached video shows the compass aligning itself (it's a kind of boring video)