Accurate Ball Launcher PVC

thingiverse

In my physics classroom we study projectile motion with accuracy and consistency being key. However, accurate projectile launchers that deliver reliable results come at a steep price ($200+). This has led to students sharing a limited number of launchers, hindering the overall learning experience. To address this issue, I designed a launcher using materials that cost less than $5, making it accessible to my classroom. In addition to plastic, you will need a large spring (Menards part #88228, 13/16 x 3-1/4 compression spring) and a 5-inch section of 1" schedule 40 PVC pipe. To launch the projectile, a paperclip is used to hold back the plunger. A swift yank releases the plunger, propelling your projectile forward. I used a 1/2" ball bearing, achieving a consistent distance of around 11 feet with an error margin of about 6 inches. Some challenges I encountered while developing this launcher include: PVC sizing inconsistency - I had to adjust the scaling percentage depending on the batch of PVC to ensure accuracy. PVC not being perfectly round - Each piece has slight oval imperfections, causing uneven hot spots on the plunger. Springs not producing equal launches - Even with multiple springs, results varied significantly. Poor gluing techniques leading to launcher disassembly during launch - Ensuring a strong bond between printed parts and PVC is crucial. Securing the launcher in place proved tricky, so I designed a bracket that uses a nut and bolt to clamp it to another surface effectively. Thanks to our school's affordable 3D printer (Monoprice MP Select Mini), we were able to print a dozen of these launchers for under $200. Although they don't match the accuracy of traditional launchers, they still provide reliable results.