Maximizing Power and Arrangement of Electromagnets in a Gauss Gun

[burtonlang]

For a high school Physics project, I am supposed to create an electromagnetic device (like a generator, a motor, a Magnetohydrodynamic boat, etc.) I was thinking about building a Gauss gun, but was wondering if I could replace the individual magnets with electromagnets. I have a bunch of 1/2" by 2" bolts, and I have access to a bunch of magnet wire. I coiled wire around one of the bolts until it was about an inch in diameter, and hooked it up to a 9v battery. It's magnetic, and is able to suspend about two or three 1/2" steel balls in a vertical line. What do you suggest to make my electromagnets more powerful, and how should I arrange them to work optimally in a Gauss gun?

 

[burtonlang]

Any suggestions at all? It's not firing, but all the electromagnets work individually. What might I be doing wrong?

 

[confinement]

You need at least two preferably more electromagnets in a line, and you need to activate them one after the other, with the activated section of magnets just ahead of the projectile during the firing. If you turn on all the magnets at once then basically nothing will happen.

The magnetic field strength is proportional to current, so get your hands on a 5 amp power supply and shield your wires from skin contact.

 

[burtonlang]

I have five in a row, right now. What do I need to do to activate the magnets at different times? It would be rather inconvenient to manually flip a switch for each magnet at the exact right time... Is there some kind of switch I can use that the ball can activate without causing too much (better yet, any) decrease in speed?

 

[pallidin]

Hmmm, look at this link and scroll down to the heading "Construction" and look at the animation on the right: http://en.wikipedia.org/wiki/Coilgun

Is that what you are trying to do?

Or, do you have in mind this: http://scitoys.com/scitoys/scitoys/magnets/gauss.html and your effort in replacing the magnets with electromagnets.

The reason I ask is that two entirely different design approaches would be used.

 

[pallidin]

Here's a few youtube vid's using just NIB magnets and steel ball bearings. Are these types of designs the ones you wish to use electromagnetism to replace the magnets?
Or do you have something else in mind? Anyway, if you haven't seen some of them before, enjoy!





http://www.youtube.com/watch?v=epf1AUvG32M&feature=related

http://www.youtube.com/watch?v=I0OZ7-PbGBE&feature=related

 

[burtonlang]

Yes, the plan is to build something exactly like those, with electromagnets.

Actually, the Science-Fair-type-thing that this was for was yesterday, and I ended up just building an ordinary Gauss gun, using steel bearings and neodymium magnets. It was extremely successful and was one of the most popular projects. However, I would still like to build the electromagnetic equivalent.

What kind of switches should I use so that the balls activate the electromagnets?

 

[pallidin]

Excellent. This clarifies your efforts. I have to go to work, but should be back tomorrow or the next day and will try to help.