MaestroMatt
Well-Known Member
- Joined
- 18/11/08
- Messages
- 257
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Hey there,
I have just built myself a stirplate for my yeast starters but am having a little problem with getting the whole thing to operate properly, so I though I would just chuck it out there and see if anyone could help.
My stirplate consists of the following:
- 12V computer case fan (ball bearing I believe)
- 25K variable resistor (Potentiometer)
- plain switch
- 12V power adapter.
The circuit works so I know it's not a wiring thing but when I flick the switch and start turning the variable resistor around it takes almost 3/4 of the revolution before the fan starts spinning and then it spins too fast for the stir bar. It's like it is not actually ramping up the power but suddenly turning on at that power level. Any suggestions with troubleshooting this one?
Also, I have salvaged a couple of rare earth magnets from a HDD and attached one of them to the fan. For some reason, at a good range away from the magnet, the stirbar spins well for a little while then starts to wobble off centre and eventually pop out of rotation.....weird... The flask is dead centre on the magnet and the magnet is as centered on the fan as I can get it....any suggestions of this one as well?
Thanks for all your help.
Once I get it working properly I will put up a guide of how I did it....not that it is any different from a lot of those around at the moment.
Cheers!
MM
I have just built myself a stirplate for my yeast starters but am having a little problem with getting the whole thing to operate properly, so I though I would just chuck it out there and see if anyone could help.
My stirplate consists of the following:
- 12V computer case fan (ball bearing I believe)
- 25K variable resistor (Potentiometer)
- plain switch
- 12V power adapter.
The circuit works so I know it's not a wiring thing but when I flick the switch and start turning the variable resistor around it takes almost 3/4 of the revolution before the fan starts spinning and then it spins too fast for the stir bar. It's like it is not actually ramping up the power but suddenly turning on at that power level. Any suggestions with troubleshooting this one?
Also, I have salvaged a couple of rare earth magnets from a HDD and attached one of them to the fan. For some reason, at a good range away from the magnet, the stirbar spins well for a little while then starts to wobble off centre and eventually pop out of rotation.....weird... The flask is dead centre on the magnet and the magnet is as centered on the fan as I can get it....any suggestions of this one as well?
Thanks for all your help.
Once I get it working properly I will put up a guide of how I did it....not that it is any different from a lot of those around at the moment.
Cheers!
MM