What happened with my stir plate???

[sar_dog_1]

I made a stir plate from scratch and with a 2L flask and a 1" stir bar, all tests were perfect. I had a full vortex with water and today I made my very first starter. I was able to get a decent vortex with it and was running fine for about two hours. all of a sudden it started making a rumbling noise and all I can do is get the wort to spin. no vortex!!!

anybody have any idea what is going on?

frusterated.......

 

[BrewCityBaller]

I made a stir plate from scratch and with a 2L flask and a 1" stir bar, all tests were perfect. I had a full vortex with water and today I made my very first starter. I was able to get a decent vortex with it and was running fine for about two hours. all of a sudden it started making a rumbling noise and all I can do is get the wort to spin. no vortex!!!

anybody have any idea what is going on?

frusterated.......

Yes, your stir plate threw the stir bar off. It's probably sitting on the edge of the flask somewhere.

Pick up the flask and turn off the stir plate. Look at the bottom and shake the stir bar back towards the middle. Then turn the plate back on and don't turn it up so fast. Problem solved.

 

[mrduna01]

What voltage are you running to the fan? Over heated maybe? Either way a vortex is not important. As long as the yeast are kept in suspension you'll be fine.

So many beers... so little time.

 

[MikeInMKE]

Maybe the stir bar got thrown to the side and it's just rattling around as the magnet poles spin by it?

I also could get quite the vortex with water, but no more than an inch deep divot in the wort without it throwing the stir bar.

 

[CA_Mouse]

Once you have wort and yeast in your flask, the density of the liquid is significantly different than the straight water. As long as you can get a small vortex with your starter wort and yeast when you first turn it on, you are golden. I keep mine just spinning the stir bar and rarely have any trouble. As long as I can see the yeast isn't settle out, then I know the stir bar is spinning.

 

[sar_dog_1]

I don't think it threw the stir bar. the wort is spinning pretty good. just no vortex. The noise isn't a rattle, but a low pitched rumble.

I am thinkin mabey the magnet is off center, or the stir bar is too small?

I wanted to poll all of you before I start to tinker.

I am not sure what voltage it is. I built it quite a long time ago but I used HBT to get all the right parts. well tested parts.

 

[raouliii]

How did you attach the magnet to the fan and what kind of magnet is it? Maybe the magnet is, or pair of magnets are, off-center from the fan's center of rotation. This would cause an extra vibration for sure.

The other possibility is that the fan's bushing or bearing has failed due to age/overuse or the stirplate design.

 

[Docbruw]

You don't need a vortex for a yeast starter you just need to keep the yeast stirred up. As others have stated the density of wort and yeast is much greater than water so it wont spin as fast.

 

[sar_dog_1]

Its a computer fan and a hard drive magnet. I just set the magnet on the fan and it stuck pretty well. didn't see a need for glue. I bet it is off balance.

 

[Zubius]

I rarely see a vortex, as long as its stirring it's all good..

 

[finsfan]

Try moving the fan/magnet closer or further away from the stir bar. I used small pieces of cardboard to move it closer and further away. What is in between the fan and stir bar?

 

[Docbruw]

I rarely see a vortex, as long as its stirring it's all good..

You stole my stir plate!! That cigar box looks exactly like mine.