Stir Plate bar keeps throwing off

[arborman]

I bought a stir plate off Ebay, I think the seller may be on this site. I have used it maybe 10 times or so. For the past 3 starters, it has thrown my bar to the sides multiple times. This problem never happened, and I am not doing anything different. Any suggestions or ideas why this is going on?

 

[nealperkins]

It turns out that stir bars and stir plates seem to be mated up properly. Too small or large a bar with an individual stir plate equals a problem like you have. There may be other variables like size of flask, etc. Hopefully, you have other bars that you can try.

 

[schematix]

best tip: run it as slow as possible to maintain a minimal vortex (mere dimple in the surface).

 

[kh54s10]

I have no problems in my flask from .75 liter to 2+ liters, below that it will thrown. I solved the problem by using a qt mason jar. The bottom was just flat enough to use.

 

[bennie1986]

I had this problem and found it could have been two things. First I turned on the plate before letting the bar center it self the magnet. Second, and probably made worse by the first issue, my flask was not as centered as it could have been. I was doing a 2l starter with a 1" bar and a commercial plate.

 

[Pratzie]

U can find little orings to put on each side of the stir bar. this will keep them leveled and balanced while they spin. Think of the front end of a car with two wheels instead of a motorcycle with one. More stable support from the sides instead of just the center.

 

[arborman]

Thank you guys. I'm trying to run it slowly to see if that solves the issue. One other thought I had: I left the magnet on the bottom of the flask for a day or so, before I pitched (so I would t forget to put it on), a d wondering if I magnitized the bar in a funky way?

 

[BBL_Brewer]

One other thought I had: I left the magnet on the bottom of the flask for a day or so, before I pitched (so I would t forget to put it on), a d wondering if I magnitized the bar in a funky way?

Absolutely not. Stir bars are magnetized to begin with. If you manage to magnetize it some more...all the better.