Tag Archives: opto-interrupter

Coil Gun Results and Explanations

Several months ago when describing how the build the coil gun, I mentioned that I would explain some of the “extras” that we implemented in our coil gun project. I will explain the mounting brackets and the opto-interrupters here, as well as why a coil gun works.

How it works
When a current flows through a coil of wire a directed magnet field is induced inside that coil proportional to the current. After the capacitor is fully charged we discharge the capacitor into the coil. This provides a large current in the coil thereby inducing a strong magnetic field. The projectiles that we use are made of steel which contains a lot of iron, a ferromagnetic material. The magnetic field in the coil aligns the magnetic moments in the iron which makes the iron attracted to the center of the coil. The brief discharge of the capacitor finishes before the projectile reaches the middle of the coil so the projectile continues instead of stopping in the middle of the coil. Continue reading Coil Gun Results and Explanations