[TheForge]magnet Q.

[Bruce Freeman]

Clearly, when steel goes non-magnetic, if the steel WERE a magnet it
wouldn't be afterwards.

However, any heating or hammering will reduce or destroy the magnetic
properties of a steel magnet.  

If using a magnet as part of a door latch:  

First, be aware that those rare earth magnets can be VERY strong. 
Think pinch-points when using them in a design.

Second, you may want to move the magnet itself away from the heat. 
Imagine, for example, using a horseshoe magnet as the handle on a hot
door.  The cooler handle will be less likely to lose its magnetic
properties.  But if constructed correctly, this remote handle could be
an effective latch for the door, since the magnetic forces will follow
the path of the steel.  (Constructed incorrectly, there would be no
magnetism to latch the door, however.   Avoid a complete loop.  Think:
"horseshoe" shape.)

Bruce
NJ

>>> erik at methow.com 5/13/2004 12:22:50 PM >>>
Hey Andy,

Ask your friend one other thing about magnets.  I wonder about heat, at
what
point does it drain a magnet of its magic affects?   I have never used
them on
fire doors but I know many have.  I have considered using them in the
past and
I am sure I will again in the future.

If I did I would use the 'Rare Earth Magnets' sold by Lee Valley and
others as
well.  They seem to be about 10 times stronger than the radio shack
type
magnets.

Roger Olsen
__________________________________

Gladish Family wrote:

> > 1. I have a number of assorted magnets used for set-ups, mock ups
and
> > the like...should they be stored separately, carefully aligned
> > north/south, to retain max  pull ( suck?) or is it not a problem
just to
> > toss them in a box with their friends?
>
> My understanding is that magnets are manufactured by applying
overwhelming
> magnetic fields (i.e. really really huge!) to a previously neutral
chunk of
> metal, and that heat or overwhelming magnetic force are the only ways
that
> magnets lose their pull, other than physical deterioration.
> I have a friend who sells magnets for a living- I'll ask him.
> Andy G.
>
> _______________________________________________
> Manage membership or unsubscribe at:
> http://mailman.qth.net/mailman/listinfo/theforge 
> theforge mail list group photo site is
> http://www.photoaccess.com 
> Login:  blacksmithblacksmith at hotmail.com 
> password:  anvil
> ___________

_______________________________________________
Manage membership or unsubscribe at:
http://mailman.qth.net/mailman/listinfo/theforge 
theforge mail list group photo site is
http://www.photoaccess.com 
Login:  blacksmithblacksmith at hotmail.com 
password:  anvil
___________