thunderfvck
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My Hotplate/Stirrer, A PIECE.
Hello.
I bought a hotplate/stirrer awhile ago on ebay, it works well. Heats up nicely, etc. The only problem is the damn stirrer. I stole a stirrer from
class yesterday and I brought it home (very excited) only to find that the stirrer doesn't actually stir until it's at the 4th setting. At
this setting the spinner spins VERY fast. In liquid it stirs nicely, at 4, but I'm concerned that it may be too violent. There isn't any
splashing going on or anything, but are there some reactions that need a slow spin in order to proceed well? For example, if I wanted to make an
explosive and I needed to stir a mixture or whatever, would my stirrer spinning at such a fast rate cause any BAD problems?
Is there anyone who has had this problem? Does anyone know how I might fix it?
Thanks.
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Organikum
resurrected
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Vary the distance between flask and hotplate - use a heating bath etc.
The transmission of the magnetic forces depends strongly on the right distance.
I dislike the stealing btw.
But thats just me.
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thunderfvck
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Stirrers are too expensive for my blood. THey have like literally more than they need anyway, they won't suffer a loss.
I've just noticed something with this piece of decaying carcass, underneath the hotplate, there's this thing that starts spinning when the
stirrer is put on. The damn thing doesn't even start up until I hit the fourth setting. And what really sucks is that this damn thing will
sometimes go WAY TOO FAST for my liking, without me even adjusting the speed. It's retarded. Like, it will be going smoothly, then WHAM,
everything gets out of hand and I have to put down the setting, then it stops, and I have to go back to four to start it up, then after awhile it does
it again. Piece of garbage. I'm guessing I will need to have this bastard fixed up. Can I bring to sears or something, they like to fix
electronic stuff...?
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vulture
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How big is that stirrer bar?
Ever heard of inertia?
BTW, stealing can not be advocated. Magnetic stirbars can be had for cheap on ebay too.
One shouldn't accept or resort to the mutilation of science to appease the mentally impaired.
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thunderfvck
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Yes, cheap. Yes, ebay. They often sell them in packages of like 5 or whatever. I only need one. Something like 20$. Meh. Anyways.
The stir bar is pretty small. About a centimeter in length I suppose.
We have a bunch of hotplate/stirrers at school and none of them behave as radical as mine does. I think I'll bring it in.
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guaguanco
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Stolen chem equipment always misbehaves. It's a karmic reaction...
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Geomancer
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Maybe God hates you for stealing. If your school has too many of the things, ask to borrow one. What's wrong with the stirrer you actually own,
anyway? As for stir bars, 20USD is not that much for most people. Or you could make your own (ceramic magnets probably have moderate chemical
resistance).
I must admit I have never taken apart one of these, but the diagrams I've seen show a motor turning one or more magnets that couple to the
stirring implement. If this is how yours works, it shouldn't be hard to fix. Or build one yourself.
I suppose one could make a solid state stirrer. I actually tried this once. I made an array of 6 electromagnets (formed around nails) laid out
either radially or vertically in a hexagon (I may have tried both, it was a while ago). I them drove them with 12V 60Hz current such that adjacent
nails were driven in antiphase. I tried to use this arrangement to spin ground up bits of cheap ceramic magnet. The device was a miserable failure;
the "spin mass" only vibrated a bit, and I couldn't keep the magnets cool enough (IIR). I probably could do much better now, though.
What do you NEED a magnetic stirrer for anyway? Overhead stirrers are easily rigged.
Once again, stealing is abhorent, especially from publicly funded educational institutions. I did it twice (from a private school), that I recall
in high school. Even though I only stole a few dollars (if that) worth of stuff (a few inches of magnesium ribbon and a couple of cover slips for
microscopy), I wish I hadn't. Very much.
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thunderfvck
Hazard to Others
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Magnetic stirring is just so simple. You put the stirrer inside, turn the stirrer on and you're set. Besides, the hot plate I own has a stirring
function, so why not make use of it.
I only have one stirrer, the one I took from my class.
Anyways, do you think I'd be able to have it repaired at Sears or some other place which deals with electronics? I mean, I'm sure they
aren't asked to repair hot plates very often, so they probably wouldn't be accustomed to the mechanism of it. But these guys know there
stuff so...So what do you think?
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chemoleo
Biochemicus Energeticus
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Lol guys take it easy on him. Although, it is not so good to steal, isn't that more of a 'gentlemans crime' in this case? It's not
like he went to a shop and started stealing a discman, or the odd unlocked car. Just a friggin magnetic stir bar, of which one gets accidentially
flushed down the sink every other day, in every lab in the world.
Sure it's no justification, and none of us are trying to advocate it. I'd bet though that everyone of you has done *worse* things than
stealing a stir bar, such as dumping a girl and making her cry for several days (I consider that worse). So maybe god will hate you too (including the
girl)  - and as for that, dumping someone also gives ya bad karma
Back on topic... Just take your stirrer apart, and use an ohm-meter/voltmeter and have a look at the dial by itself. Should be easy to fix, comon,
you dont need to give it to a repair shop! Radioshack/Maplin/whatever will have similar ones with which you could replace it. Maybe it's just a
bit of dirt that prevents current from flowing. Bring on the mad science skills!
Never Stop to Begin, and Never Begin to Stop...
Tolerance is good. But not with the intolerant! (Wilhelm Busch)
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BromicAcid
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Back in the day I made my own magnetic stirrer. Took a small strong circular magnet and broke it in half. Took a circle of wood and chisled
out the edges to accomidate the magnet and glued it in place. Took the circle of wood and epoxied it to the end of a small electric motor from Raido
Shack. Got an adaptor for the power supply and a rheostat to vary the voltage. Even got a project casing there that I put it all in with a nice
on/off switch. It served me faithfully for years till a beaker of nitric bursted on it. The casing being made of some crummy alloy.... it
didn't last long. Stirbars I bought from eBay during a dutch auction where I was grabbing them up for $.99 and I've picked up a couple from
my school. Not really stealing as I was responsible for them and I paid full value for them out of my breakage card, I used to use them like credit
cards, lol, is it stealing if you pay for it?
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Polverone
Now celebrating 21 years of madness
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Breakage cards... how interesting! If I'd had those in school I bet a lot of things would have "broken." Can you "break"
reagents too? I hate paying hazmat shipping.
PGP Key and corresponding e-mail address
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Magpie
lab constructor
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stealing supplies/chemicals
I agree with Geomance on this. Over the years I have lifted a minor item here and there and inevitably came to wish I hadn't - it's the
"conscience" thing you know.
At one time I was responsible for a complete Buchii Rotovap. Its various parts had gotten mislaid in various places so I brought them all home to
inspect and reassemble. You can bet the thought crossed my mind that it might just as well stay at my place as no one but me would miss it. But at
$5000/ea there was no way I was going to not take it back. Not only would my conscience crucify me but if caught I surely would have lost my job.
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thunderfvck
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Chemoleo, you tell me to repair it myself, but I must confess that I am terrible when it ocmes to electronics. Whenever I try to "fix"
something, I usually end up breaking it to pieces.
Besides, I really wouldn't know where to start. You tell me to take it apart, look at the dial and check with an ohm/volt meter. What should I
expect from this? Anyway, needless to say I really wouldn't know what I'm doing. But I do need practise, I just hope I don't destroy
the $100 item.
You will all be pleased to know that I also stole 2 graduated cylinders (10 ml) and a 125 ml erlenmyer flask. Not to mention a spatula, and a few
pasteur pipettes on different occasions. I was considering taking a buchner funnel but I decided that 4 items was enough for one day. Let the flaming
begin!
The way I see it, if they won't miss it, who cares. I'll have more use for it anyway. They literally have thousands of the items I have
chosen to take. More than enough to satisfy the student's needs. Of course I wouldn't even consider stealing someone's personal goods,
but school property is always up for grabs. I'd feel guilty if someone was like, oh no, where's my erlenmyser flask? I really needed that
for my experiment today (sulking). That's really not the case. They probably couldn't care less if a few items go missing, they probably
won't even notice considering the mass quantities of the glassware they have. Anyways, let me burn in the damned fires of hell. So flame me as
you will, but remember this, I will have the last laugh as I plot mass destruction with the master overlord, Satan!
MUAHAHAHHAHAHAHAHAHAHHA. LET ME BURN, O FOUL BEASTS! YOUR TIME OF RECKONINING WILL SOON FALL UPON YOU! MUAYAHAHAH!! EAT THE STENTCH FROM MY ANUS AND
BLEED IN HEMORHOID DEATH! WIMAYAGAHAHAYYAHUAUAHAH
*may regret my behaviour tomorrow morning, after the alcohol's worn off...*
[Edited on 19-2-2004 by thunderfvck]
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Saerynide
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Lol, how on earth do you managed to take so many things at once without getting seen? Surely, you must be sneaking in on non-lab days huh? 
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Hermes_Trismegistus
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Has anyone mentioned yet that stealing is wrong ?
Stealing from your school is like stealing from your parents, It seems OK when you're a kid cuz no-one gets hurt and they have an inexhaustible
supply of wealth..........then you grow up.
anyway, try the most obvious things first. Open the stirrer cabinet (box) and look for any loose connections, especially around the switch and
selector.
If that doesn't turn the trick, note the make and model number of the stirrer itself and look on the manufacturers website for a trouble shooting
guide or if necessary write the company directly.
First they'll give you the rigamarole about how you shouldn't try to fix it yourself (because of liability issues) but just lie and say
you're a tech and assume all risk.
(you seem to be an accomplished thief so I'm sure lying is old hat eh?)
---------------------------------------------------
Here is the design for an improvised overhead stirrerhttp://www.rhodium.ws/chemistry/equipment/overhead.html#
Improvised magnetic stirrer.
http://www.rhodium.ws/chemistry/equipment/magstirrer.html
Here is the source for really cheap stirbars (although you can get much cheaper if you order in quantity from here or other places)
http://www.rare-earth-magnets.com/SearchResult.aspx?Category...
You buy these magnets, they're pretty chemically resistant but if you wanna distill strong acids or some such, you'll want to coat with a
thin layer of two-part epoxy from the auto zone.
For larger stirbars you can use the epoxy to glue two together.
Attach one to a wooden dowell and epoxy the whole thing for a good stirbar grabber (or borrow thunderfvk, he's a good stirbar grabber)
Arguing on the internet is like running in the special olympics; even if you win: you\'re still retarded.
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Organikum
resurrected
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Oh my god!
I absolutely didnt want to start this "stealing" debate.
I only told my opinion.
I didnt even say: Dont do this again.
I just told I dont like it.
And thats my fucking right to have such an opinion.
No morals were brought up by me, no hellbound, nothing.
After somebody is sober again and has reinstalled his brains he might consider this:
- Now you know ppl dislike this - dont tell. Or are you carrying a transparent in school: I am a thief?
And consider this:
Here on this public board you wont find anybody who advocates stealing in any way. Nobody is so stupid to do so.
One exception.
You.
And now kindly edit your posts in a way that you dont look like somebody who is proud of being a thief and who boasts with this fact on a public
board.
Of course I will delete this post in followup and the sun will shine again.....
Got it?
This is called:
A GOLDEN BRIDGE
addon:
btw, the evil overlord this week is vulture, next week I am on duty again, satan will come back in august I believe for doing his week of devilish
reign.
If you ever should go to hell you would be surprised. No fires, no! Aircondition! You would have to do the cleansing of the toilets at start, is
understood. But not for long, just for two or three eternities, dont mind........
[Edited on 19-2-2004 by Organikum]
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chemoleo
Biochemicus Energeticus
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Organikum, maybe, just maybe, he wasn't boasting, possibly he just sought to wind you up.
And he certainly achieved that
| Quote: |
Here on this public board you wont find anybody who advocates stealing in any way. Nobody is so stupid to do so. |
Are you saying 'noone' advocates it openly because it is potentially dangerous to the person concerned (or even to the
forum itself), but secretly you all stole the odd stir bar yourselves, for your personal use? Gotcha!!!
The evil thief has unwilingly revealed himself
PS sorry I couldnt help myself org 
Edit: If this upsets you I will happily delete that message... just thought it's too funny to not to point this out 
[Edited on 19-2-2004 by chemoleo]
Never Stop to Begin, and Never Begin to Stop...
Tolerance is good. But not with the intolerant! (Wilhelm Busch)
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guaguanco
Hazard to Others
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I gaveuponyourpost afterthe15thsmiley icon
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Hermes_Trismegistus
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Hmmm....Good membership here.
Thunderfvck, I couldn't help but notice that you're being flamed a little
Sometimes gently warmed and sometimes fiercely babrbequed.
Consider it an opportunity to re-examine your own personal feelings towards theft.
Flaming has happened to others on this board and sometimes (especially by younger people) they respond with NA...NAH NA NAH NA...I do what I
want!....geri springer type of attitude posts.
I hope you don't succumb to this temptation.
and I hope you've noticed that even those who've flamed you with one breath, have offered assistance and advice in the next.
This isn't an anarchist/kiddiebomber/doper type website eh?
This is a membership of amateur scientists, (some of whom occasionally massage rules and regulations) but most of which are generally law abiding and
moral people.
I hope you have gained a better idea of the membership of this community.
Even if you've taken a little flak to earn the experience.
Arguing on the internet is like running in the special olympics; even if you win: you\'re still retarded.
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vulture
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They often sell them in packages of like 5 or whatever. I only need one. Something like 20$. Meh.
You're kidding. I've seen lots of them go away for 2€ or less.
Now, I'm going to close this topic, because:
A) It's going to derail into a flame war
B)Thunderfvck won't accept any advice unless it's perfectly in accordance with his principles.
One shouldn't accept or resort to the mutilation of science to appease the mentally impaired.
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