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Homemade stirplate question

I made my own stirplate but it isn’t spinning the stir bar. The bar just has one ended stuck to the bottom of the flask. The magnet is from a hard drive and I broke about 1/3 of it off while removing it. Is this the source of my problem? The magnet does look centered too. Thanks.

how far below the flask is it?

The cigar box lid is 1/4" and maybe a 1/16" air gap below that. The magnet is stuck to the bottom of the flask at one end.

Try flipping the magnet. Or perhaps try out a larger stir bar. If that doesn’t work I’d recommend trying another mag. (each hard drive has 2)

Is it not spinning the bar at all or is it throwing the bar shortly after starting?

Not spinning at all. Just pins one end to the bottom of the flask and it sorta quivers.

What size stir bar are you using? I first tried the 2" and it didn’t work at all. I had to purchase a 1" and it works great.

Sounds to me like the fan you are using may not be powerful enough.

Or the magnet is too powerful and/or too close to the stir bar.

It is a 1" bar and later on today I’ll try it with more of a gap between the two. The fan should be powerful enough because it still is spinning right?

This may have been a typo, but just to be clear, the magnet should be attached to the fan. So when the fan spins, the magnet spins with it. That’s what makes the bar spin in the flask.

Taking what you wrote literally, if the magnet is stuck to the bottom of the flask there’s nothing to make the magnet spin, so the bar won’t spin either.

My last post was worded poorly. The stir bar was stuck to the bottom of the flask directly over the magnet which is on the fan. Today I replaced the partial magnet with a non-broken one and it works fine!

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