bought a 80mm 12vdc computer fan at compusa for $10 complete with fancy lights...but the best feature is that it has a switch with three settings
connected the fan to a 9vdc converter, attached to fan to a homemade wooden box that was sitting around, screwed a small piece of pyrex ($3 at HD) on top and I am now stirring a starter for my vienna lager
the best thing about my stirrer is that i didn't need to connect a rheostat (I ignored the on/off switch) - simply plug it in on low and the magnets catch the stir bar easily
the three setting switch for the fan is currently on low and works great with a 1 inch stir bar and a 1 liter flask
life is good
connected the fan to a 9vdc converter, attached to fan to a homemade wooden box that was sitting around, screwed a small piece of pyrex ($3 at HD) on top and I am now stirring a starter for my vienna lager
the best thing about my stirrer is that i didn't need to connect a rheostat (I ignored the on/off switch) - simply plug it in on low and the magnets catch the stir bar easily
the three setting switch for the fan is currently on low and works great with a 1 inch stir bar and a 1 liter flask
life is good