WTB: Magnets for my DIY Stirplate

[Kayos]

The shipping is killing me on these. I can't find anything for less than $12 in shipping even if the magnet is only a few cents. Know any local stores that may have them? Have a couple you want to sell me and drop them in a padded envelope?

Help?!?!

 

[KCBrewer]

I've got quite a few old hard drives laying around I could yank a few out of for you. I usually pay just under $2 for something that weighs a few ounces for first class in a padded envelope. Just PM me and I'll let you know the cost.

 

[ultravista]

Are you talking about the fan's magnet or the stir bar that goes inside the beaker / glass?

 

[weizen]

http://www.harborfreight.com/10-piece-rare-earth-magnets-67488.html

 

[wyzazz]

I was in Home Depot yesterday and to my surprise they had some Rare Earth Magnets in the Hardware section by the Cabinet/Door hardware. 3 different sizes.

 

[wildwest450]

How would we know a local store, when we don't know where you live? In the south, Hobby Lobby carries them.

 

[Kayos]

That link leads me to my next question.....if you use round magnets, how do you get the stir bar to not just spin in one place? Am I missing something here.....don't you need the bar shape of the magnet on the fan to to get the stir bar to make the vortex a bit and not just sit in one spot?

Would you offset the round magnet a bit?

 

[wildwest450]

That link leads me to my next question.....if you use round magnets, how do you get the stir bar to not just spin in one place? Am I missing something here.....don't you need the bar shape of the magnet on the fan to to get the stir bar to make the vortex a bit and not just sit in one spot?

Would you offset the round magnet a bit?

Slaps head. You need two round magnets on the fan, and a stir bar in the flask to create the vortex. The round magnets hold the stir bar in place and spin it.

 

[smokinghole]

That link leads me to my next question.....if you use round magnets, how do you get the stir bar to not just spin in one place? Am I missing something here.....don't you need the bar shape of the magnet on the fan to to get the stir bar to make the vortex a bit and not just sit in one spot?

Would you offset the round magnet a bit?

I used the Harbor Freight magnets as I have a local store. I did a stack of three that I used epoxy to hold together. Since the stir bar has a north and south pole you need to use separtely placed magnets. They also have north and south which in the case of the harbor freight magnets is the top/bottom. So in order to properly use the round magnets at harbor freight one needs to have north up and the other needs to have south down. Otherwise you will repel the stirbar off instead of spinning the stirbar. Once you have all the pieces a monkey can figure it out.

 

[Homercidal]

I used the Harbor Freight magnets as I have a local store. I did a stack of three that I used epoxy to hold together. Since the stir bar has a north and south pole you need to use separtely placed magnets. They also have north and south which in the case of the harbor freight magnets is the top/bottom. So in order to properly use the round magnets at harbor freight one needs to have north up and the other needs to have south down. Otherwise you will repel the stirbar off instead of spinning the stirbar. Once you have all the pieces a monkey can figure it out.

Don't you mean, one will be North up, and the other South UP?

 

[wildwest450]

Don't you mean, one will be North up, and the other South UP?

Meh, it really doesn't matter, those little suckers are so strong, they wont let you make a mistake. Just have the stirbar close by, they'll flip right where they need to be.

 

[smokinghole]

Yeah too much up and down in those sentences.

 

[Anthony_Lopez]

Have you tried K&J Magnetics? www.kjmagnetics.com

I have the N42-BX042 magnets.

 

[Kayos]

Have you tried K&J Magnetics? www.kjmagnetics.com

I have the N42-BX042 magnets.

Yes. $0.92 per magnet. $12 to ship!

 

[Kayos]

Slaps head. You need two round magnets on the fan, and a stir bar in the flask to create the vortex. The round magnets hold the stir bar in place and spin it.

Uh.....needed that slap....thanks.....I think I get it.

 

[mbtech]

I took apart an old hard drive. You will find the magnets glued into place. Just get a metal putty knife or something ultra thin under the magnets (two of them) and work them off. I'm sure there is a thread out there somewhere for a DIY stir plate using these, a washer, and old computer case fan.

 

[jburdett]

I got mine in a Micheal's craft store for around $3. They're neodymium magnets or rare-earth magnets. The store employee looked confused when i asked for them and responded "Do you mean those wicked strong ones? Yeah we got some of those"

 

[mr_goodwrench]

I got mine in a Micheal's craft store for around $3. They're neodymium magnets or rare-earth magnets. The store employee looked confused when i asked for them and responded "Do you mean those wicked strong ones? Yeah we got some of those"

That is exactly where I got mine. SWMBO practically lives there in the scrapbooking section.

 

[Kayos]

Cool. I will check there. Thanks all!