Stuck Grinder Bowl
This seems to be a widespread problem on units manufactured in 2007 and later.
Unplug the unit from the AC outlet. Remove the six screws that hold the lower plastic cover on the motor
base (four screws are hidden under the adhesive rubber footpads). This
exposes the lower end of the motor shaft, which has a slot in it. By
inserting a flat blade screwdriver into the slot and holding the
cutting blades with a rag or a wad of paper towel to avoid cutting
one's fingers, it is possible to twist the shaft back and forth about
90 degrees. You may need another person to help, because one needs to
perform this twisting action while pulling the motor base away from the
grinding cup and blade assembly.
you get the @&%$#! thing apart, reassemble the motor base. (With
the slotted motor shaft, why didn't the designers simply put a hole in
the plastic base so one could stick a screwdriver in without
disassembling it?) Plug it into the wall outlet and use a small object like a toothpick or
matchstick to activate the recessed motor switch so you can spin the
motor without the grinding cup in place. Use the blunt edge of a small
snap-blade utility knife as a scraper to gently scrape the plastic pin
of the motor shaft as it spins, much as one would work a wood turning
lathe. Periodically check the fit of the brass hub of the grinding cup
on the plastic pin. Continue to shave the pin until the grinding cup
slips onto and off the pin with no resistance. Take care to machine the
pin uniformly from top to bottom; avoid making grooves.
this mechanism worked properly when my grinder was new about 18 months
ago and suddenly decided to get stuck this week is a bit of a mystery.
The unit in question has been used since it was purchased exclusively
to grind flax seed, but the ill-fitting pin normally doesn't come into
contact with foods, anyway. There was no obvious evidence of swelling
of the plastic due to heat from the motor or oils from seeds. Since the
blade and hub are free to travel up and down on the plastic motor shaft
pin a bit, I suspect that on occasion the blade doesn't settle properly
and the clutch doesn't engage, allowing the pin to spin in the brass
bushing until it starts melting, and then the hub settles so that the
clutch is fully engaged. This may happen in a matter of just a couple
of seconds of operation. Once that happens, the pin conforms to the
microscopic grooves inside the brass bushing, allowing it to still turn
slightly relative to the motor shaft, but locking it on so that it
can't come apart. If Cuisinart had made the pin more tapered and the
hole in the brass bushing to match, much like a Jacobs taper on an
industrial drill press spindle, this would be much less of a problem.
BOTTOM LINE: Before loading the grinding cup and starting the grinder,
push the blade hub down with your finger to make sure the clutch is
Apr 14, 2008 |
Cuisinart SS Grind Central, removable bowl...