Demagnetization risk of Neo magnets in repel mode?

[JackH]

Honk,


I built a wankel motor a couple years ago.  This motor used repell mode.    It would only run two days before the magnets were gone.     I used the same size magnets in it through out.   And yes I used NEOs(N48).

I never did figure out what caused them to go bad, but they did.    Maybe the rpm or something, I dont now.

I know I'm going to catch hell for this, but I tryed it, didn't work.


Later,,,,,,JackH

[IronHead]

Repel motor using N50 here  ran for 4 days and  dead.

Alittle bit about demag, Sorry its not much .

http://video.google.com/videoplay?docid=1681787127575536292&q=Walter+Lewin&total=91&start=0&num=10&so=0&type=search&plindex=3

[Liberty]

message deleted

[mikestocks2006]

Repel motor using N50 here  ran for 4 days and  dead.

Alittle bit about demag, Sorry its not much .

http://video.google.com/videoplay?docid=1681787127575536292&q=Walter+Lewin&total=91&start=0&num=10&so=0&type=search&plindex=3

IronHead
Thanks for the link.
On a side note also on the same page, this is very interesting:
M.I.T.-Walter Lewin- Complete Breakdown of Intuition - Part1
http://www.youtube.com/watch?v=eqjl-qRy71w&mode=related&search=

and definitely this, where he actually does the experiment and measures/records the 2 Vs !

M.I.T.-Walter Lewin- Complete Breakdown of Intuition - Part2
http://www.youtube.com/watch?v=1bUWcy8HwpM&mode=related&search=

Possibly useful for the TPU and related replications too?
Good stuff

[Honk]

Iv'e been having two N50M neos in repel mode for 3 month now and I measured them yesterday to
see if they had lost any of their strength. Well, they hadn't lost anything. They were as good as new.

The originally measured 0.51 tesla on the surface and 3 month later in repel they still measure 0.51 tesla.
Maybe they won't become demagnetized when just sitting still. Perhaps motion is required???
I might build a rotating repel test machine later on to see if they can handle that to.