I’ve owned a BODUM Bistro Coffee Grinder for a number of years, and aside from occasionally running rice through to clean the grinding surfaces haven’t had any issues with it. Recently bought some new beans which are much oilier than ones I usually get, and after running most of them through ended up with the grinder failing to work.
The failure was the mechanism sounding like it was okay for roughly a second, then the motor straining under load before what sounded like plastic gears jumping teeth. At this point I turned it off. Running it with an empty hopper worked fine, adding anything (either beans or ground coffee) to the hopper caused the load issue. On the third attempt it also had stopped self-feeding from the hopper, and trying to gently push beans/grounds through caused the stoppage above.
David Hagman has previously torn down his grinder and posted a video on YouTube showing the internals. I couldn’t see any obvious part of the internals that would be related to the failure I was experiencing, so I decided to start with cleaning it out and then continue with a strip down if that didn’t reveal anything.
To start with the hopper came off, then the top half of the burr grinder lifts out vertically leaving a worm screw standing proud. I first started gently tapping the grinder unit upside down to free any stuck coffee, then escalated to a small bottle brush. There was still enough grounds stuck around the base of the screw mechanism I couldn’t reach with a narrow brush, so I switched to a bamboo barbequeue stick to loosen grounds and then tip them out.
After clearing out most of the base of the worm gear, whilst I had the unit upside down tapping out the loosened grounds I looked up the chute the grounds fall down into the jar normally to find it was blocked solid with ground coffee. Some gentle rodding with the skewer to break it up and eventually I could see from the grinder mechanism through to the end of the chute.
Once that was clear and everything removable had been thoroughly cleaned and dried, I reassembled and ran rice through it a few times starting with a really coarse grind and fed the result back through the hopper, getting finer each grind. Grinder now works flawlessly, and I guess lesson learned about checking the chute to make sure it’s clear more frequently.