Hackathon on a Water Pump for the Fall Play by Frances Harrington ’19

Post by Frances Harrington ’19

Early this year, Ms. Bisi approached us to design and build a working hand pump for the Fall play. The Fall play this year is The Miracle Worker which is about Helen Kel

ler’s journey. Although Ms. Bisi had already purchased one, the design was faulty as it leaked and required priming which meant inconvenience. Priming a pump means eliminating anyexcess air from the chamber. Should the pump have required priming on stage, actors would have to worry about this imp

ortant part of the play not working when the scene has already starter.

We split into three groups and spent our hour and a half designing hand pumps. First, it was important to educate ourselves on the way hand pumps work. This required research initially. We used the internet to search for explanations on the workings of a successful hand pump.

Hand pumps require a chamber for the water with a handle attached. When the handle is brought up, the pressure increases within, so when the handle is pushed back down, the water pulls up and out through the spicket. Additionally, the water needed to go back into the chamber so the water did not fall on the stage or need to be replenished.

After we felt we understood how it works, we researched hand pumps that had already been built to identify any important points to remember or any potential design flaws. Additionally, others researched blueprints for hand pumps.

Towards the end, all of our findings were combined to make a design that produced a working hand pump lacking leakage and requiring minimal priming. During her lunch time, Ms. Bisi came to listen to our presentations. Currently, Sebastian Singh ‘19 is working on building the actual pump.

Moment of Inertia Project Update – By Olivia Danielson ’21

Post written by Olivia Danielson ’21

On April 3, 2018, Dr. Call presented a project for a couple of the 2021 fellows. He needed six 3D-printed models, comprised of five cylinders and one sphere, to demonstrate inertia for his Physics class. Inertia is the resistance of a body to change its momentum. What Dr. Call is going to demonstrate with our models is the moment of inertia, which is a measurement of how hard it is to change the shapes’ rotation rate. The way to measure that is by using this equation:

I = ∑m(i)r(i)2

The models were either solid or hollow. Solid meant that it had a 5%-25% infill, which could be changed when it came time for the shapes to be sliced. For a hollow circle, it needed an inner cylindrical hole that extended through the bases of the cylinder, creating a hole from the top to the bottom of the Cylinder.


We created all of these shapes using TinkerCAD, which is a “3D design and modeling tool” that one can use online. After we finish designing the models through TinkerCAD, we slice the shapes in Curia, which means getting the shapes ready to be printed. The printer that we use is 

a 3D printer called Ultimaker 3 Extended. Three out of the five cylinders and the sphere have the same radius of 5cm while the other cylinder has a 7cm radius. For all the cylinders except for one, the mass should be within 10g of each other. We aimed for around 103g. So far we have four cylinders done and one that is currently being printed. We plan to finish this project in early October.