Originally Posted by Yunus
I havent read every post here but I made a stir plate in the DIY fashion. The magnets I used were kidney shaped ones out of a Hard drive. Very powerful. I found that putting 1 magnet in the center of the fan worked but I have yet to get it working with 2 magnets. Just an FYI for anyone having trouble. Also I use a very small stir bar, about 1/2". It can make a funnel in 2l of water though.
The trick to getting two magnets to work, is first getting the polarity of the two magnets right, the second is getting the center line of the two magnets to line up correctly with the center line of the fan..... otherwise, the stir bar will "orbit" around the center of rotation and ultimately be tossed.
1. magnets must be equidistant from the center of the fan
2. magnets must have the proper polarity alignment
stir bar (- +)
mag 1 (+) (-) mag 2
3. center line of magnets must align with center line of fan.
I also found it helpful to space the magnets so the end of the stir bar was even with the center of each magnet
hope that helps