Recently I had the misfortune of my Cuisinart CEK-50 cordless electric carving knife becoming defective. It was running continuously, even when the trigger wasn’t held down, and wouldn’t stop unless held at a specific angle.
As always with cheaply-made plastic consumer crap, the culprit was a 1¢ piece of plastic on a $3 component.
Specifically, the microswitch connected to the knife’s plastic trigger had its tiny actuator snap off. This meant the knife was running all the time unless the actuator was forced out of the switch (into the “off” position) by gravity.
What follows is a very rough guide to repairing the knife. It should take about an hour.
- A soldering iron and solder.
- Heat-shrink tubing.
- A Torx 9 bit.
- A Philips 3.5 bit.
- A pry tool and/or spudger.
- A replacement microswitch (assuming that’s your issue) – it’s a Merchant CMm SM-51 16(4)A 125/250VAC, but any 16A switch of the same form factor should do.
- Unscrew the one visible torx screw at the base.
- Pop the clamshell casing using your pry tool:
- Two small tabs – front and back – hold the base cap in place.
- Two small tabs – front and back – hold the top cap (very tightly) in place.
- Several plastic tabs up each side of the case hold the body in place.
- Undo the four visible Philips screws – two under the bottom cap and two under the top cap – to fully release the case.
- Inside, on the other side of the knife’s trigger, you’ll see the white plastic blade holder mechanism. The microswitch is underneath it.
- Remove the four screws from the white plastic and two screws in the black plastic just down from it.
- There’s a small black plastic “bridge” which acts as the safety slider – gently pry it off at each side.
- The white plastic can now lift out.
- On one side there’s another small black plastic arm which is what connects the trigger to the microswitch. Remove it.
- Pull the microswitch out from under it.
- De-solder the existing wires.
- Put your new switch in.
- Apply heat-shrink tubing and solder the wires up again.
- Re-mount everything the way you found it.
You can test your new switch works before soldering by holding the neutral and live wires to their terminals and pressing the actuator.