The technology behind 3D printing is being used for a vast range of activities -- printing eye cells to help develop a future without blindness, to create firearms, casts and prosthesis, and more. Added to the list is a small printer made out of CD-ROM drives that, using a needle and type of ink, prints 3D designs inside of JELLO.
The 3D printer was developed by the folks behind SpriteMods using old CD-ROM drives to print designs in JELLO shots for a birthday party. The printer works with parts harvested from the drives and mounted on a wood board, with a syringe needle being mounted on the contraption where three stepper motors move it around. The liquid is pushed into the JELLO using a standard syringe with plunger.
The final device isn't the most beautiful unit ever hacked together, but the point wasn't so much beauty as it was getting a functional printer together to make some stylish JELLO shots. Because of the parts used and its small size, the entire unit is powered using a 10v laptop battery, meaning it is portable enough to be moved about from one location to another.
The last part, then, is the ink, which obviously had to be edible and of a consistency that kept it from running in the JELLO. To achieve that, the hacker used a mixture of banana liquor, corn starch, and food coloring. The "ink" was heated in a microwave to get a gel-like consistency. The result is the ability to print two shapes in a cup of JELLO, and bragging rights long after the party ends.