4 October 2013
While doing nothing in
particular, I decided to make another peanut butter stirring machine
because I'd traded the last one for a Model T Ford ignition coil to put
on the Model T Ford Coil Tester.
This is made from an old Seagate ST225 20 Meg MFM hard drive
that was just sitting around waiting patiently to be put back to
work. I think that other HDDs could possibly be made to work
using this circuit but I haven't tried any other types.
The 2013 Peanut Butter Machine.
The machine is used to slowly rotate the jar of natural peanut butter
to mix the oil back in after it's been sitting around for a
while. The first two machines I made ran very slowly, turning on
the order of one revolution every 30 seconds or so. This one runs
much faster doing about three or four revolutions per minute.
Surprisingly, it does a nice job even though I didn't think it would
mix the peanut butter unless it was going slow enough for the whole
glob to move from end to end.
At the new speed, the peanut butter doesn't move much with each
revolution but does mix well. It takes about 12 to 24 hours to do
In the photo, you can see that the jar is held in place in the 0.100"
thick sheet steel bracket by being sprung into the holding tabs.
With a little practice, the jars can be insert and removed with very
Here's a movie:
Fiddling with the spindle motor
coils, I came up with a simple circuit that would adequately drive the
motor although it does have to be given a push in order to start.
The schematic is below in case you have one of these old drives sitting
around and want to waste some time playing with it.
Schematic of the motor driver.