dangerous amateur
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Magnetic stirrbar shapes for viscous stuff
Hi guys,
is there a different shape of stirrbar than the standard cylindrical one, that is better suited to stirr syruplike stuff with some insolubles?
Barbell or egg style...?
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careysub
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Samarium-Cobalt stir bars are used for this purpose.
Don't know about the shapes. It would seem that although shorter, squatter ones would spin more easily in a viscous medium, they would also provide
less stirring, while you actually need more.
Most Sm-Co sir bars are the traditional cylindrical shape (though sometimes an octagonal "cylinder"), often with a pivot ridge, so that may be the
best compromise.
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dangerous amateur
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Yes, I know about these extra strong magnets.
But I mean just the influence of the shape, no matter what kind of magnet is in there.
| Quote: |
It would seem that although shorter, squatter ones would spin more easily in a viscous medium, they would also provide less stirring, while you
actually need more. |
A big chubby stirrbar would have more magnet weight in him and thus more conveyable force like a thin stick of the same diameter.
Hmm.
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careysub
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There is a limit to how far stir bars can be pushed. When the going gets really tough people have to go to overhead stirrers (but you probably knew
that).
Check out the selection of types here:
http://www.stirbars.com/
Another consideration is the power of your magnet stirrer. You can make a super-powerful magnetic stirrer to drive the stir bars also.
Here is also a useful discussion of stir bar types and principles:
[Edited on 18-9-2016 by careysub]
Attachment: labwarenews-3-1.pdf (1.3MB)
This file has been downloaded 324 times
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ecos
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overhead stirrer may help
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dangerous amateur
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Thanks.
Yeah I know about overhead stirrers. I just dont have the money now...
And working with a cordless screwdriver sucks.
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