Has anyone tried this?

[lwh]

Just wondering.

http://fdp.nu/mikelldevice/thedevice.asp

The whole story looks really dubious to me.  I can't see why it would work, but at the same time, I find the image of the magnet-covered donut form interesting somehow,    so I've been playing around with some 3mm neo cubes stuck to some MDF, using bits of an old ceiling fan as a base for it to spin on.

It's spun repeatedly by itself for up to almost a quarter revolution, but I don't know why.  It could have just been a strong repulsion action followed by a comparitive lack of magnetic reaction. 

There's what I'd call a wavy corrugated effect you can feel when slowly rotating the disk, where you can feel the magnets repulsing each other line by line.  When you  let the disk go at the top of one of these waves or corrugations it will often jump up over the next wave and keep going for a little while.  As I said, the furthest Ive seen it go was about a quarter of a revolution (or something under 90 degrees).

I'm not really sure if I want to keep dabbling with this, so just thought I'd share the information before I put it away.  It might help prevent others from unecessarily covering the same ground.

Here are some pictures.  I've since redone the donut with the magnets on a more angled spiral, but have found it less effective.

   

Les.

[Liberty]

Nice pictures and work.  The design seems to be similar to a Perendev magnet arrangement where more magnets are in attraction mode than in attractive lock or repel.  Golden ratio...  I have found that it takes away the rotational strength of a device if any magnet is allowed to fully encounter an opposing magnetic field.

[Rosphere]

I spent about $50.00 and a couple weekends making my, "sound theory," permanent magnet motor.  That was when I learned about the unanticipated sticky spots.

If it were easy to make a permanent magnet motor work then everyone would be making them.  I have not completely lost my faith that it is possible.  I still enjoy entertaining the idea.  However, my threshold of construction initiation is much higher now.  I would rather pulse some coils these days.

I echo Liberty's endorsement of the Golden Ratio.  My latest musings entertain a concept very similar to this post involving Golden Spirals and Fibonacci Numbers:

If you look at the end of a pine cone you will see eight rows of nubs spiraling in one direction and thirteen rows of nubs spiraling in the opposite direction.  Eight and thirteen are Fibonacci Numbers.  Every nub of the pine cone belongs to both of these counter rotating spirals at the same time.

(If you look at all of the spirals in this proposed design series at the link posted, you will see only one direction of spirals taken into account.  Yet, the individual magnets are like pine cone nubs in that they are points, not lines.  We may find a connecting spiral pattern in the opposite direction of the current design by accident, but I do not think that it was a design intent.)

Once the memory of my previous failure fades, I may attempt to pursue this line of thinking.  Perhaps I will use an actual pine cone and glue magnets directly to the nubs.  Size, shape, and orientation of the magnets are undecided at this point.  Perhaps it will come to me in a dream.

[CLaNZeR]

Excellent work LWH

You must have hell of alot of patience, that must of taken ages.

I played with laying spirals out on Plexiglass a few months ago, like the small model he shows, but it did not do alot must admit.

Keep up the good work

Regards

Sean.

[lwh]

Thanks for your replies.

It's funny you mention the counter-rotating spirals on the pine-cones Rosphere, as I noticed the same thing developing on the later, more angled, magnet arrangements I tried (not pictured).  And it did make me wonder if it was somehow crucial to the design. 

To deliberately and accurately lay out the magnets in a way that keeps both spirals in a proper line would be very difficult though, and I don't think I have the patience for trying that at the moment.

Les.