Summary

A Vacuum Cannon, that will launch printable projectiles to near the speed of sound. https://vimeo.com/135655056

Instructions

Besides the printable parts, you will need :
--Single stage vacuum pump.
--Acrylic tube ID=40mm OD=50mm.
--Vacuum tube.
--Packing tape min 50mm wide.
--Eye and ear protection!

Using the cannon:
Insert a projectile in the end with the hose connector.
Add one or two layers of packing tape at each end, depending on tape type, and desired pressure. If using two layers apply them perpendicular to each other.
Remove anyone or anything at either end of the tube.
Lower the pressure with a vacuum pump, single stage is sufficient.
Puncture the packing tape in the end with the hose connector with a sharp knife, POP!

Printing the end caps:
Print them with thick walls or 100% infill to make them strong and air tight. Glue them on the ends of the acrylic tube. Remove the print support under the hose connector.

Printing the projectiles:
This is trial and error. I printed them single walled, with 4% infill. In Cura you can move the projectile around on the build plate so that you get two perpendicular infill walls exactly in the middle. This way they will weigh around 7g, and be quite strong.

Customizer:
The end caps are customizable for any tube ID/OD.
The bullets are not yet customizable, but you can easily make your own.

Disclaimer: This build is intended for physics professors or similar teaching physics. It will accelerate the projectile to speeds near the speed of sound. I am not responsible for any injuries you inflict on yourself, others or things.

Project: Vacuum Cannon

Vacuum Cannon

            <div><p>Project”  description in the Custom Section, as follows (this is the key part!): Add a Custom Section and change its title to “Project: Title Of Your Project”. Then add Text blocks with subsection titles to match the boldface sections listed below.<br>Objectives: List what students would be expected to learn from participating in this Project.<br>Audiences: List the grades, ages, or skill levels that would be appropriate for this Project.<br>Preparation: List anything students that should already know about or have done before starting this project, and/or any necessary technology, resources, or materials.<br>Steps! Finally, here’s the part where you can describe your Project idea! Describe the flow of your Project, including any step-by-step guidance that you can provide.<br>Results: Describe what students should have designed, made, printed, or achieved at the end of your Project, and any ideas you have for grading or assessment.</p></div>