Hamilton Beach Coffee Grinder (Type CM04 Model 80344)

The coffee drinker of the house has upgraded to a burr-type grinder for coffee beans, retiring this well-used unit which is now on the teardown bench.

It’s more accurately a coffee bean chopper, since it spins a set of blades to break them apart.

Cracks have started developing on its blade hub, which might be related to why one of the two blade tips drag on the bowl carving a channel. (Slightly out of focus in above picture.)

Mechanically, I’m curious to see implementation details for the cord management system built into the base. I expect the rest of the machine to be a shell around an AC motor spinning the blade.

I peeled off three rubber feet expecting to find fasteners hidden underneath, but there was nothing.

The base was actually held in place by a plastic retaining mechanism in the center. After popping off its smooth cosmetic cover, we could grasp the retainer to unlock it with a twist. Then the retainer could be removed, which released the base.

Power cord reel is visible after base was removed.

This little piece of plastic towards the end stops power cord from unwinding further, bumping up against a retaining ring. This retaining ring is held in place by four hooks. Gripping the ring with pliers and twisting clockwise a few degrees to slide past the hooks allowing removal of ring and power cord reel.

I was surprised to find a slip-ring style arrangement of metal rings and fingers. I had expected to see a very clever arrangement of bent and creatively routed wires to support power cord reel rotation without the parts count and complexity of a slip ring. I was wrong: it’s a slip ring.

Underneath the slip ring we see the first (and it turns out, the only) signs of traditional fasteners. Three Philips-head fasteners around the outside keep the motor frame in place.

What looks like a flat-head fastener in the middle is actually the motor shaft.

Putting a flat-head screwdriver on the motor shaft allows us to control its rotation and remove the blade. After blade removal, the motor could be maneuvered out the bottom.

With the motor out of the way, we could pry on plastic clips holding top ring in place. This one shows several scars from my efforts to release it.

With the ring removed, the control circuit slides out the top.

I had not noticed the safety interlock switch until I saw wires leading up to it. This ensures the lid must be in place before the blades would spin. It’s pretty clogged with coffee grounds which will eventually cause it to become unreliable.

The heart of the machine is a motor with the following printed on it:

HONDARAYA
Model:
UD1N00075DF
120V 60Hz

A web search found Hondaraya Engineering is a Hong Kong company, small enough of an operation that web search engines helpfully suggested I probably meant Honda the Japanese manufacturing giant. I wonder if Hondaraya was responsible for just the motor or if they were contracted by Hamilton Beach to engineer the entire grinder.

I was impressed by how this machine was designed. At its core, a pretty simple machine: a motor spinning a blade. The design and engineering team nevertheless devised a compact cord management system at the bottom. And it was held together almost entirely by cleverly designed plastic retaining mechanisms, the only exception were the three screws holding the motor frame in place. The lack of glue should mean easy assembly and repair, though replacement parts are not sold for this device. I never did find a good explanation why one blade tip has been dragging on the bowl. If a replacement blade were available, it would have been easy to replace and test to see if that would address the problem.

2 thoughts on “Hamilton Beach Coffee Grinder (Type CM04 Model 80344)

  1. Do you still have the lid for this? I’m searching for one. It’s my favorite coffee grinder but my lid has developed cracks. I would pay you for it. Let me know. Thank you.

    Like

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