Magnets - how to store? - HobbyTalk
 
LinkBack Thread Tools Search this Thread
post #1 of 11 (permalink) Old 09-12-2010, 10:30 AM Thread Starter
Lifetime Member
 
LeeRoy98's Avatar
 
Join Date: Jul 2005
Location: Small town, USA
Posts: 1,010
Magnets - how to store?

I've been wanting to ask this question for some time... how should you store magnets? Should a pair of tjet magnets be left connected for storage... like this () ? If you have a large number, should the north poles be nested together and the south poles nested together... like this ((((((())))))? Should the magnets be kept seperated?
What happens if you nest and have enough for a couple layers in a drawer, are you affecting the magnetic field?
I know that years ago my father had a large horseshoe magnet with a metal "keeper" plate at the end. My father indicated that was to maintain the magnetic fields in the magnet? Should the magnets be kept seperated with a metal plate at the end... like this (| |)?
Any magnet experts on Hobby Talk?

Thanks,
Gary
www.marioncountyraceway.com
LeeRoy98 is offline  
Sponsored Links
Advertisement
 
post #2 of 11 (permalink) Old 09-12-2010, 01:11 PM
HobbyTalk Pro
 
Join Date: Aug 2003
Posts: 4,512
Keep them like you show them here: ((((((())))))

You want them to be stored such that they are attracted to each other and either touching or have an easily magnetizable path (soft iron) between the attracting poles. That's the purpose of the magnetic keeper, to provide a magnetic path, or magnetic circuit, between the poles that are attracted to one another. Storing magnets in isolation is the next best case, and the absolute worst case is to store magnets in a repelling orientation.

I store my extra TJet magnets exactly as shown above and found that those old PC expansion slot blanking plates are the perfect size to sit them on to further enhance the magnetic circuit. It's all about closing as many of the magnetic circuits as possible.

Since we're doing lo-fi graphics ... here's the simplified model of the theory behind this. It's all related to "free poles" and I'm not talking the Lech Wałęsa type. You can conceptualize any magnetizable material as being made up of a series of tiny particles with north (N) and south (S) poles. When these poles are all oriented along magnetic lines you have a magnet. When they are not oriented or are random you do not have a magnet. When you have magnetizable material that can be permanently locked into a magnetic orientation you have a permanent magnet. How "permanent" this is depends on a number of things, and one of those things is "free poles."

Let's look at a pair of TJet magnets:

Magnet 1: (NS-NS-NS-NS-NS-NS(

Magnet 2: )NS-NS-NS-NS-NS-NS)

In your slot car motor the magnets are aligned like this with the parentheses being the magnet faces and backs:

(NS-NS-NS-NS-NS-NS( <armature> )NS-NS-NS-NS-NS-NS)

The NS pairs are the tiny magnetic particles inside the thickness of the magnet. Notice that inside the magnet every polarity pole has a mate of the opposite polarity right next to it, but on the face and back of the magnet there is either a N or a S pole by itself. These unmated poles are the free poles. The polarity of the free poles determines the polarity at the face of the magnet.

So what does this mean to magnet storage? Basically, if you look inside the magnet the internal particles all have an opposite polarity pole on both sides of them. This keeps them pretty much locked into that orientation. They have little reason to want to change their orientation. The free poles on the other hand are only locked in on one side. They can be swayed to change their orientation. One way to keep them from changing is to produce a mate for them. By placing an easily magnetizable material or "keeper" between them, a material whose internal particles can be magnetically aligned by the adjacent permanent magnet, the free poles now have mates on both sides and are now "locked in" to their magnetic orientation.

______Magnet 1__________Keeper_________Magnet 2_______
(NS-NS-NS-NS-NS-NS( [NS-NS-NS-NS] )NS-NS-NS-NS-NS-NS)

So that's the theory behind magnetic keepers. As shown above you'll still have free poles on the backs of the magnets, which is why placing them both on a magnetizable plate helps even more because it creates other paths and eliminates more free poles. If you have several sets of magnets then nesting them together helps as well as long as it does not create any mechanical stress due to the shape of the magnet that can break the magnet. If you try to nest a TJet magnet with a very strong neo magnet it may very well snap the TJet magnet in half. I learned the hard way.

I store my traction magnets stacked in a magnetically attracting orientation on big neo magnets. This seems to keep them at or near their peak but I have no illusions of this substituting for a good zapping. Be careful though, I have seen ceramics nearly demagnetized by monster neos. Never try to force magnets together in a repulsive orientation, never.

I hope this makes sense.

Last edited by AfxToo; 09-12-2010 at 01:15 PM.
AfxToo is offline  
post #3 of 11 (permalink) Old 09-12-2010, 01:23 PM
HobbyTalk Pro
 
Join Date: Jan 2006
Posts: 2,519
Great. Now I can add magnet theory to electricity in my list of headache producers. LOL!

Actually that was very informative and I was able to follow about 95% of what you said; and if I can follow 95% of it, that means it could not be clearer.

Thanks...Joe
Grandcheapskate is offline  
post #4 of 11 (permalink) Old 09-12-2010, 01:26 PM
Top Dog
 
ParkRNDL's Avatar
 
Join Date: Mar 2002
Location: Southern Central Pennsylvania
Posts: 6,353
WOW. ya kinda lost me there at the end, but i followed for a while... and it makes me feel good that i store my magnets like this too (((((((())))))))

thanks for the explanation. i might try the expansion slot plate trick, too...

--rick
ParkRNDL is offline  
post #5 of 11 (permalink) Old 09-12-2010, 10:50 PM Thread Starter
Lifetime Member
 
LeeRoy98's Avatar
 
Join Date: Jul 2005
Location: Small town, USA
Posts: 1,010
Thanks for the excellent answer, it all makes sense. I have been storing them correctly, I just never knew why!!

Gary
AKA LeeRoy98
www.marioncountyraceway.com
LeeRoy98 is offline  
post #6 of 11 (permalink) Old 09-13-2010, 01:19 PM
Elder Statesman
 
Join Date: Feb 2005
Location: Near Chitown
Posts: 1,457
Shock and heat are the 2 largest killers of magnet strength so avoid the habit of letting them snap together.

The AFX "EX" Super G+ pit displays had a small metal bar to store the car and AFX even suggested this would keep your magnet strength strong.

As for car/magnet storage, some guys in my club found that you could glue small strips of skid banding steel into your pit box trays perfectly to hold onto your cars and also keep the magnets attracting.
Slott V is offline  
post #7 of 11 (permalink) Old 09-13-2010, 02:49 PM
Elder Statesman
 
Rolls's Avatar
 
Join Date: Jan 2010
Location: Belmont, CA USA
Posts: 1,668
Great answer, yes; but Gary, I think a lot of people have wondered about this and as it turns out, we now know there is a very right and wrong way to store magnets (and cars with magnets). So I really appreciate your initiative in raising the question in the first place so the experts could shed light on it - it's a good topic and now it's good content!

Or in thesaurus-speak: Thanks for initiating the query that enabled the experts' elucidation for our enlightenment.
Rolls is offline  
post #8 of 11 (permalink) Old 09-13-2010, 03:03 PM
Top Dog
 
ParkRNDL's Avatar
 
Join Date: Mar 2002
Location: Southern Central Pennsylvania
Posts: 6,353
Quote:
Originally Posted by Rolls View Post
Or in thesaurus-speak: Thanks for initiating the query that enabled the experts' elucidation for our enlightenment.
Yeah, what he said.

--rick
ParkRNDL is offline  
post #9 of 11 (permalink) Old 09-13-2010, 05:00 PM
Lifetime Member
 
resinmonger's Avatar
 
Join Date: Mar 2008
Location: Torrance, CA
Posts: 2,232
Quote:
Originally Posted by Rolls View Post
Or in thesaurus-speak: Thanks for initiating the query that enabled the experts' elucidation for our enlightenment.
Dood! Now my head, like, really hurts...
resinmonger is offline  
post #10 of 11 (permalink) Old 09-15-2010, 04:24 PM
Elder Statesman
 
Join Date: Jan 2000
Location: AZ USA
Posts: 586
This is how I store my extra magnets. It's just a piece of 1/2 inch metal conduit. Is this OK experts?
Attached Images
File Type: jpg Magnet_Tree.JPG (300.8 KB, 58 views)
buzzinhornet is offline  
post #11 of 11 (permalink) Old 09-19-2010, 04:06 PM
Member
 
Join Date: Oct 2003
Location: Denver, Colorado
Posts: 300
Send a message via AIM to Voxxer
This is from Geoff C. in FRHO. He sent the first part to my BlackBerry and I deleted it. I will try to get the first part back.


some pics attached

my steel plates are known as 'mending plates' at the hardware store.
These are about 1 3/4" x 5" and fit the parts box just about right as they are easy to get out
when sitting on an angle.

The magnets on the steel hex-bar are placed how I interpret the tips from AFX-TOO and in this
orientation, the magnets repel and I don't believe I will leave them that way.

The toe-to-toe matched pairs and N and S separated stacks prefer to line up that way
and stick to the plate just fine.

This is how I store them.


Geoff

Thanks

Voxxer
Attached Images
File Type: jpg P1020429-magnet-plates.JPG (186.8 KB, 30 views)
Voxxer is offline  
Reply

Bookmarks

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the HobbyTalk forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in









Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Show Printable Version Show Printable Version
Email this Page Email this Page
Search this Thread:

Advanced Search



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome