Gravity is Optional - EddyCurrents
Magnets and Aluminum Rings

Everyone knows that aluminum is not attracted to a magnet. We are taught that at an early age. These experiments use aluminum rings and magnets.

Getting started | The Force Field | Strings | Creating a gap

Getting started

After playing with aluminum cans, I was ready to try the magnet on anything. Dave had recently ripped apart some scrap disc drives to get the magnets. Among the left over parts were a bunch of aluminum spacers .. so I grabbed a few to see if they might be fun.

These spacers are rings with about a 1" inside diameter .. just the right size to fit over a 7/8" magnet :)

So I tried the usual stuff

The Force Field

Hold the ring just above the magnet and try to drop it over a magnet.

I tell the kids that I have created a force field .. just like on Star Trek. When the shields are up, the ring will not go over the magnet.

If you hold the magnet, and pull the ring on and off, you can feel the force.


Well, that was very successful .. so I wanted to try suspending one of these on a string. Wow !

Try, really try, to put a magnet thru the ring .. without touching the ring.

After you give up, use 2 hands and put the ring over the magnet. Now, slowly pull the magnet out from the center of the ring. Remember, aluminum is not attracted to magnets. (I am sure that you were taught that. I certainly was.)

Well, it is already on a string .. so play. If you have been reading these pages in order, then you already know what to do. Move the magnet sideways to make the ring spin (just like for the can on a string). Hold the magnet still, and watch the ring stop spinning.

Creating a gap

Using a jeweler's saw with a fine blade, put a slot in the ring. That's right, cut all the way through one side of the ring. (This is why you need several rings .. not just one.)

Please be careful cutting metal. I have used power saws (a band saw and a scroll saw) to create the gaps. In both cases, I wore eye protection and used a piece of wood to hold the rings. The band saw made a gap that was too easy to see (too wide). On the scroll saw, my extremely fine 4-zero blades would not even scratch the rings .. so I just used a coarser blade. The same blades work in the scroll saw and the jeweler's saw.

Now repeat all the experiments above.


Author: Robert Clemenzi
URL: http:// / EddyCurrents / Rings.html