Barry's Coilgun Design Site

Current projects: Click here to see my latest coilgun, my best coilgun or my levitator.
Also try out my RLC Simulator and Inductor Simulator.

What is a coilgun or gauss gun? It accelerates a piece of iron or steel down a tube. The tube runs through a series of electromagnetic coils (like solenoids). There are no sparks or noise or impressive side effects (or parts to wear out). Some careful timing circuits energize each coil in sequence. The principle of magnetic attraction draws the projectile along at rapidly increasing speed.

Why build a coilgun? It demonstrates many basic concepts of magnetic machines. A coilgun is foremost an example of a solenoid. These appear practically everywhere, from car door locks to doorbells, from diskette drive ejectors to fuel injectors. The only difference is that most solenoids limit the range of travel, and usually have a spring return. A coilgun is also an example of a simple linear motor.

A coilgun is scalable to very large applications, possibly as large as a mass driver to put payloads into orbit. It's a keen space-age toy. It has no moving parts -- there's the magic of invisible forces at work. It requires no special construction techniques or unusual tools. Winding coils is fun and relaxing (at least for the first few!). Even small coils are remarkably powerful.

You can also learn about magnetic levitation here. These pages include complete design details for several maglev demonstrators which levitate small iron parts. Read all about it and see levitation pictures.

Jan 18, 2012 - I applied a 24-hour blackout to the top pages of this coilgun website to help raise awareness of SOPA and PIPA legislation, and to ask citizens to contact their U.S. congressmen. The proposals attempt to address the growing problem of foreign websites posting copyrighted content of Big Media without permission. But the bills are fatally flawed: they create a powerful censorship tool with a technically unworkable definition of "foreign" and "domestic", a broad and vague definition of "just cause", and it breaks DNS lookup by introducing major security holes. Congress is even more tech-illerate than the media companies.

Jan 17, 2012 - Updated the Rare Washington Counties page about ham radio licenses and how they are distributed around the state. My previous figures were from 1999 and this data from the FCC database brings it current as of January 2012.

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