Rehab for Coffee Grinders: Nuova Simonelli Edition

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I hit rock bottom on Wednesday night. 8PM found me in the parking lot of a local gas station, furtively palming money over to another Kansas City coffee addict for a new-to-me coffee grinder. Let’s review for a second… I currently have four coffee grinders in my kitchen with a 5th one on the way from a Kickstarter (Handground… are they EVER going to ship?!). In all fairness, four of them are manual grinders and the fifth is a POS that I have to sift fines out of to use, but it works until I can justify something better.

On a whim I went on Craigslist, saw a Baratza Encore for $100 that I was interested in (if I could get it for $80) and then spotted what I ended up buying… a Nuova Simonelli MDX for a ridiculous, and I mean ridiculous, price. The seller ended up being KC coffee guru, Ben Helt, so that made me feel way better that the grinder wasn’t stolen or completely broken. He said it needed to be cleaned and needed a new set of burrs. Burrs for this grinder are only $60, so no big deal.

Oh, I forgot to mention that the MDX retails for $1100 and it is intended for restaurants and cafés!

She's tall.
She’s tall.

This thing is serious, serious overkill for the home kitchen. First of all, it sits about 7 inches taller than the bottom of my cabinets, so I have to remove the hopper even to keep it in the kitchen. Otherwise she’d have to live in the basement and that’s no life for a beautiful Italian espresso grinder! Second, the brochure recommends this grinder for shops producing up to 190 cups of coffee… per hour. LOL The gigantic hopper holds up to a kilo of coffee beans. Running a few tests, the grinder retains about 7-10 grams of coffee in the chute and doser mechanism. With my little Hario hand grinder, I put 18 grams of coffee into it and 240 cranks later, I get 18 grams out of it. I need to use almost 30g of coffee to get enough into my portafilter, making it downright wasteful. But that grind! Imagine the most consistent coffee grind you’ve ever seen, then make it 10 times more consistent. Bellissima!

The retained grinds issue is not a problem in a coffee shop that is making espresso after espresso after espresso, probably using the same coffee for weeks or months at a time. For someone like me, who changes coffees everyday and has limited amounts to review, it’s ridiculous, but I still love my new Nuova Simonelli. She’s a peach.

This grinder has two features that make it AWESOME, especially in a production environment. First, it’s stepless, meaning that there are infinite adjustments that can be made to the burrs to bring them closer together and further apart. You aren’t relegated to the little clicks that most grinders make. If you need to tighten or loosen the burrs “a smidge” you can. And you will. The second feature that’s super cool is that the LOWER burr is the one that gets adjusted. As such, it is super easy to pop the upper burr off, clean it up really easily, and re-install it and the machine will still be dialed in. That’s a great feature and if I was in a shop I’d be rocking one of these, for sure. Of course I would need one for each espresso blend, another one for pourovers, another one as a spare… LOL

But, boy, was Ben right when he said she needed a good clean up. It took me four hours to take her apart, clean, and put her back together. Let’s take a look…

According to the manufacturer’s plate, my MDX was born in 2008. Judging by the pound of grounds that fell out of every orifice of this thing, as well as the cemented on oil/grounds combination that I literally had to chisel away from some parts, this poor grinder was probably never cleaned. Scary.

What’s cool is that I was able to do this project with simple tools:

  • A small Philips screwdriver (like the little ones for eyeglasses)
  • A large Phillips head screwdriver
  • A medium Phillips screwdriver with a long shaft
  • A flat blade screwdriver of decent size
  • A pair of 10mm wrenches or a 10mm wrench + a 10mm socket wrench
  • Soap, water, rags, toothbrush and a variety of other brushes
  • Vacuum cleaner

The only thing I wasn’t able to do was detach the lower burr from the shaft and get into the motor and really clean it well. There was a TON of coffee INSIDE this thing and I vacuumed it out well, but I would’ve liked to take it completely apart. Probably unnecessary, so it’s probably good I didn’t!

It took me 4-5 hours to do this project. You’ll end up with a decent amount of little screws and things, so label your parts and take lots of photos so you remember what goes where.

Cemented on coffee residue EVERYWHERE
Cemented on coffee residue EVERYWHERE

I started by taking off the upper burr cover and the upper burr assembly. This was super easy. The cover pries right up with fingernails or a flat screwdriver and the upper burr assembly can be removed with the Phillips screwdriver. Rather than go into too much detail about how to do that, Seattle Coffee Gear has a great video showing the basic cleaning operations of this grinder including taking the burrs apart and such. Watch it!

I washed all the plastic parts I could in soapy water. This included the hopper and the little trapdoor in the hopper that releases/plugs the beans from entering in the burr chamber, the doser lens, the plastic parts on top of the doser lens) as well as the aluminum thing that holds the upper burr. Since the burrs are steel, I removed them and cleaned them with a dry toothbrush.

Dirty burr chamber. Barf
Dirty burr chamber. Barf
Underside of the top of the doser lens
Underside of the top of the doser lens
Doser lens... had seen clearer days
Doser lens… had seen clearer days

The doser lens is a bit of a PITA to take off. Remove the top of the lens first (there should be three little tiny screws holding it down). You’ll remove the top of the lens with a little trap door that catches the grounds as they blast out of the burr chute and a little plastic covering that keeps that trapdoor in place. Then you need a long-shafted screwdriver to get at the two screws holding the lens in place. The video above shows this very well.

What lurks beneath the burrs?
What lurks beneath the burrs?

Once the doser lens is off, you get to see the burr chute. Check mine out! There’s about a pound of coffee cemented in there. Tasty stuff, no doubt!

Nouva Simonelli 8
Burr chute – dirty as $%^!

Here’s the burr chute as seen from the burrs’ point of view after cleaning. Much, much better!

2015-08-27 08.29.14

Probably the hardest part of the project was taking off the portafilter holder and also taking the doser itself off. That thing was full of SO much cemented grounds it was horrible. Also very difficult to remove. You need the 10mm wrenches for both parts I just mentioned. You also have to take the bottom of the grinder off and you’ll be AMAZED at how much coffee falls out. Get that vacuum in there really well if you can.

Belly of the Beast
Belly of the Beast

Be careful with the doser mechanism. It has all sorts of springs and moving parts. It didn’t explode on me but I wanted to take it further apart to really get in there. Probably a bad idea. You can easily take the fins off from the inside and really clean it. The underside is disgusting, but doesn’t matter because that won’t end up near your portafilter or in your drink, so don’t take all that mechanism apart because it doesn’t really matter. Vac it out, get compressed air and toothbrush in there, though.