Stir Plate not working now?

[TheMan]

My question is pretty simple (I think)...I made my own stir plate. It worked perfectly fine with water. I tested it extensively with water. It worked flawlessly.

Fast forward to last night, I made a starter and I could not spin the stir bar for the life of me. Is the added thickness of the starter creating the issue? What can I do to fix it?

I use a 1 gallon glass jug with a 2 inch stir bar. Hasn't had any issues yet.

Thanks in advance!

 

[nutty_gnome]

I had this problem this weekend with my 1 liter starter. First I chased down the loose wire that was causing intermittent operations. Then, when it became apparant that the starter was too thick/viscous for the low-voltage power brick I was using, I commandeered a higher voltage unit to use. That did the trick. I don't recall which voltage I bumper it up to... maybe 9 volts up from 3? Good Luck!

 

[oceanselv]

The viscosity of the starter will be higher than water. However, the stir plate should be able to overcome the viscosity increase. Have you checked all the connections? Does the stir plate work when you place water in a container and stir it? If all else fails, take a sterilized spoon and mix the starter and try the stir plate again.

 

[TheMan]

I have a 14 volt power suppy, so that shouldn't be the issue. Would adding another magnet help at all? smaller stir bar?

It has worked flawlessly until I switched from water to yeast starter, I guess maybe I'll try stirring water in another container when I get home just to verify...but I tested it tons, to avoid this specific issue I'm having lol.

 

[nutty_gnome]

The viscosity of the starter will be higher than water. However, the stir plate should be able to overcome the viscosity increase.

I thought that would be true, but the fan kept stalling until I gave it more juice. *shrug*.

 

[TheMan]

An update:
Still no success. I raised the fan closer to the jug. This helped. I can get it moving for about ten minutes, but then the stir bar falls loose. Then I start it back up for another ten minutes or so and it falls loose again...I don't understand why. I don't feel like I can center the magnet any better.

I swapped to a lower power supply, to a 9 volt from 14 volts just in case the magnet was spinning TOO fast for it with the 14 volt. This appears to not matter.

Any other advice?

 

[GilaMinumBeer]

Does your stir bar have a pivot point?

I use a 1 gallon jug too and could never get the bar to spin. It would just jostle around. Finally, I placed a dip tube o-ring over the bar for a center pivot point and it works flawlessly now. Can produce a vortex at least halfway through a 1 gallon starter at full speed.

 

[TheMan]

It does not have a pivot point. Just a smooth stir bar. I will try the dip tube o-ring though. I've got plenty lying around.

 

[TheMan]

Gilaminum, that worked fantastic!!! Thank you! Hope this helps anyone else that has a similar issue. I can't go full speed, probably because of my high powered 14 volt supply, but it goes near full.

But my stir plate works. Thanks everyone for your input!

 

[johntangus]

I'm having a similar problem. Bar not spinning through thick starter. I can up the power from 6 to 12, but what the heck is a dip tube o-ring?

 

[BeernuT100]

I'm having a similar problem. Bar not spinning through thick starter. I can up the power from 6 to 12, but what the heck is a dip tube o-ring?

The o-ring that is found on a dip tube from a keg. Any o-ring should work as long as it fits snug on your bar.