Magic Jug

thingiverse

A jug that "magically" refills itself. After you pour all of the contents out, you can set it down, and a few seconds later you can pour water from it again. In reality the jug has a double wall, with a small hole between the inner and outer chambers. A hole on the outside can be blocked with a finger while pouring, keeping the contents of the outer chamber from spilling into the inner chamber. Printer Settings Printer: Kerrby Rafts: Doesn't Matter Supports: No Notes: I suggest printing with thick bottom and top layers. This model is supposed to be scaled up by either 150% or 200% before slicing. How I Designed This Designed using rhino. I drew the outer shape of the jug, then revolved it to get vase-like shape. Then I copied the vase shape turned on control points, and scaled the parts of the vase that didn't touch the rim. With control points on for both entire shapes, I pulled one of the control points to make a spout. I joined the two pitcher shapes together by adding a lip that attached the two. I used an offset surface to thicken the walls, then used some boolean operations to punch holes for air and water flow. Project: Magic Jug Objectives: The objective of this project is to get students to think critically about a problem. Audiences: This project would work best for grade school students. Probably best for students 4th grade and under. Preparation: No preparation is necessary for this project. It would probably work best at the beginning of a unit or semester. Steps! Before presenting, fill the jug with water prior to presenting the jug, have a clear glass you can pour the jug into. Have some kind of patter for while you are presenting the jug. For younger students you could make up a story about where you found the seemingly magic jug. For older students you might want to present it in a less imaginative way. Put your finger over the hole on the outside of the jug and pour all of the water from the main chamber into the glass. Set the jug down, so that the hole on the outside cannot be seen by students. After a few seconds have passed, and the main chamber has refilled, pick the jug up with a finger plugging the hole on the outside. Repeat the pouring process several times until the outer chamber is nearly empty. Have students hypothesize how they think the jug works. You can have them individually try to figure it out, or work in groups. Results The goal is to get them to think critically about why it seems like the jug is capable of refilling itself. The project does not need to take a long amount of time and would work well for introducing students to a class or as a lead in for another project. I suggest grading mostly based on participation.