built a stir plate from a computer fan approx (82mm.) has a rehostat wired in and magents glued onto a bottle cap which is then glued onto the fan hub. i have tried different speeds, different heights , repositioning the magnets and even two different voltage supplys..6V & 9 v.still nothing.....
all i get is the mexican jumping bean routine and then off to the edge of the flask. my flask is 2000ml and the stir bar is 1" no raised ridge
am I missing something here?