Modding the Mazzer 2.5

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#1: Post by Jean-Paul »

Thanks to Craig and his epic CNC lower vane mod shown here
Modding the Mazzer 2

I felt inspired this morning after reading it and decided to modify the Super Jolly that I just picked up. (After seeing how much spray comes out of the left side of these machines, Craig's solution seemed perfect) Most people don't have the time or tools to what he did, so here's my solution that does exactly the same thing for about $10, and a few hours of craftiness.

NOTE: the purpose of this project was to reduce the amount of stale grounds that remain in the Mazzer's doser, and to improve the efficiency of the dosing to reduce overall waste (which also increases the accuracy of the dose)

Basically I had 4 steps to this project.... dis-assembly & cleaning, lower vane mod, dispensing chute mod, and reversed cup or cone mod.

1. Dis-assembly & Cleaning
Doser dis-assembly instructions here
Cleaning was a piece of cake using Cafiza, although I wouldn't use it again on the aluminum components as it tarnishes the metal, but works like magic on the plastic and stainless.

2. Lower Vane Mod
a. The floor of the doser is not flat, it has a little raised section that the washer & lower vane sit on, so I took the bottom of the doser out and put it in the drill press with a flat stone and ground it flat enough that I was happy with the way the vane would spin tight to the bottom without rubbing too much. Once I was happy with it, I glued some fine grit emery paper to the stone and sanded it smooth.

b.Then I took the lower vane itself and filed the top of each vane to remove the flat spot on each one then sanded them smooth. (SEE before and after shot)

3. Dispensing Chute Mod
a. I clamped a piece of aluminum to the bottom of the doser, and clamped it all to the workbench. Then got some Session Savers (2 part epoxy putty) surfboard ding repair from Live To Surf and filled the hole of the dispensing chute.

b.After it dried (30 mins or so), I removed the aluminum plate, and trimmed any excess material on the top.

c. Then I drilled out a better sized hole using a drill press and Forstner bit for the new and improved dispensing chute, then filed, sanded and buffed out a smooth entrance.

4. Reversed Cup or Cone Mod
a. After looking around the house for similar diameter cup or cone to fit the top of lower vane, I found this funnel that worked perfect. I just drilled a hole in the top and cut a bolt to right length to attach where the upper vane used to attach and good to go. No more grinds getting hung up on the upper vane.

The Finished Product
Here are 2 shots of the completed product being put back together.

This picture is before any beans have been ground after cleaning.


This picture illustrates how effective these mods were. First off, there was very little spillage out of the portafilter during dosing, and second, the doser is almost completely grind free. The lower vane now literally sweeps the bottom clean.

Here's how it used to look after a grind

Bonus: By replacing the lower vane washer, upper vane, and all the other bits and pieces, then popping out the new chute, it's back to stock again (resale, blah blah).

I'm pretty stoked how it all turned out, and hope others find this useful.

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#2: Post by craigcharity »

Well done, looks really cool.

Once you make the tapered hole for the bottom there's no going back:) every time i use my friends un-modded SJ I get so annoyed with how messy it is.


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Randy G.

#3: Post by Randy G. »

I would caution about using a stone grinding wheel on aluminum. If the stone is not designed for aluminum the ground off material will build in the stone. I have been taught that this can cause the stone to explode at higher RPMs (centrifugal force, heating? I am not sure). For a job like this, at low RPMs it is probably OK, but if the stone has a buildup of aluminum in it I would advise discarding it when done.
Espresso! My Espresso! -
LMWDP #644


#4: Post by ZDUNK31 »

Great low-buck project, I'm a fan of high-tech but if you don't have access to a machine shop or the equipment this is the way to go. Nice work.