A few weeks ago I posted on this forum about perhaps finding a new machine to replace my 11 year old Pasquini Livia 90. In reading through the various sections of this forum I was, quite frankly amazed to see how far that home espresso has come in a short while. When I bought my Livia, it was one of three "top" machines for the SERIOUS home espresso connoisseur. The Livia 90, baby Gaggia, and the Rancilio "Miss Silvia" were at the time (other than commercial equipment) almost about the best you could do as far as prosumer espresso machines.
However, suggestions from some of you as to the best route to take as far as getting a good cup OUTSIDE of replacing my machine was to work on the grind and using ultra fresh coffee (I presently use Danesi Gold), before buying new equipment.
One thing that intrigued me was the Mazzer Mini standard burr to Super Jolly 64mm burr modification. Since I have a Mazzer Mini with 11 year old burrs, I decided to perform this mod.

First off, I owe a debt of gratitude to -ethorson- and his post from July 2011 "Installing Mazzer Super Jolly burrs in a standard issue Mini" Without this article and accompanying pictures, I would have never had the stones to try modding my grinder; in fact, I probably wouldn't even know you could.

I purchased the burrs from Espresso Parts and they arrived in about a week. NOTE: I only attempted this mod because I work in a metalworking environment; Lathes, Milling machines, etc. If you do not have access to a machine shop, or have a REALLY good friend that does, I wouldn't recommend this mod. If you have a lathe and drill press in your garage, and moderate to good skills with the equipment, then go for it.

In the article mentioned above, reference was made to adapting the clearly larger Super Jolly burrs to the Mazzer Mini burr carrier. Yes you will need to fabricate some rings. They could be aluminum, steel, or brass - your choice. I feel aluminum is more forgiving besides being relatively easy to machine. I went with that.

The dimensions for the rings referenced in the article were 2.175" O.D. (Outside Diameter), 2.047" I.D. (Inside Diameter) x .075" thick. I used some high precision calipers on my Super jolly burrs and found the 2.175" O.D. number to be quite adequate. The I.D. however, I chose to make 2.050" which was a good choice because the fit was perfect on the burr carriers. As far as the .075" thickness of the ring, I measured my burrs at .080" depth on the back so that's what I went with. ADVICE: Measure everything, make to existing dimensions. Remember, it doesn't have to be within one ten-thousandth of an inch accurate; it just has to fit well on the I.D. of the new burrs (slightly loose is okay), and the burr carriers, both top and bottom. Thickness should be even with or less than the depth of the back of the burr.

My rings then: 2.175" O.D. X 2.050" I.D. X .080" Thickness.




Here are a couple of pics of the burr carriers with the rings installed.



You can see in this picture why you can't use the Mazzer Burr Screw holes with the Super Jolly's; just too far off location to work.



Now for the hard part: drilling and tapping the burr carrier for the screws. I chose 8-32 x 1/2" Stainless Steel Pan Head Slotted screws that I was able to get at Lowe's. You could probably make 6-32 screws work as well but I decided to go with a bit bigger screw.

In the other fellow's tutorial on this particular mod, he had you file the ring slightly where the screws went through the SJ burr; I chose not to follow that route because the ring is just too fragile and thin in my opinion. You wouldn't want to bend or break it after spending the time to make it! Rather, I opted to put the screws in BETWEEN the ring and the edge of the hole in the burr.
Here are a couple of shots of the new screw holes:



I used a small center punch to establish the location for the screw holes. I did it by eye, but there are a few different ways to do this. -Turned out just fine.

Here are the screw locations as shown on the underside of the bottom burr carrier:


As you can see in the next photo, we are very close to the ring; actually the chamfer is touching it. If you drilled them on center of the SJ burr hole it is likely you would split the ring in 3 places.


...the underside of the top burr carrier.


Note: I chose to drill the holes completely away from the other Mazzer Burr holes and not try to use the standing "bosses" that Mazzer put in. Why? Because the thickness of the carrier at that point allows for plenty of screw "bite" into the aluminum. This view is with the screws cut to length.

On the lower carrier, beware! You don't want to drill your holes into the "sweepers" so make sure you plan ahead!


Mostly finished product. I still had to cut off the SS screws on the top burr carrier.


A couple of notes here: The bottom burr carrier is pressed on the shaft. It is not impossible to remove but it can be stubborn. You may do some minor damage to your unit in removing the carrier. I certainly did. I consider this minor, and no functionality was impaired. I had to remove the finger guard in the doser (which I then threw away), and use a screwdriver and small crescent wrenches to slowly pry the carrier off. This is the result to the machine:


I can live with the dents in the motor guard. I filed the gouges down in the sweep area so they will not interfere.

Here is the bottom burr carrier mounted back in the Mazzer.


Be careful here too; there is a small square key that keeps the burr from spinning on the shaft, if you reinstall and miss locating this this key you will have to pry the burr carrier off again to attempt a second time.

After the install I ran a box of Minute Rice through to remove dirt, sharp fines, etc., from the burrs and start to season them. If you do this, afterward you MUST take both burrs out and completely clean them. If you have an air hose it would help get out the rice flour you just made. Blow out the bottom section, doser, and top carrier well. You will likely have to take a small knife tip or sharp blade and clean the rice out of every cutting edge as it has a tendency to stick in there.
After cleaning the rice out and blowing out all traces of it, I re-assembled the burrs in their carriers and ran a couple of pounds of stale coffee through to season the carriers and further break them in. I'm sure the burrs will continue to develop over time as well.

Immediately noticed a difference in grinding espresso; slightly faster, and needed to get my adjustment down before I could make a good cup. Since the Mazzer is step-less, it allows for infinite adjustment in grind. The Super Jolly's were a good investment and in my opinion the time to put them in was really minimal for the potential benefits.

Nicely done. But next time, use this method to remove the lower burr carrier: Removing Super Jolly lower burr carrier. Much easier and won't damage the floor of the grind chamber like that.

Fantastic post on this mod! Let's hear about the results - was it worthwhile?

I'm considering the same myself and am trying to decide between two options: buying new SJ burr carriers ($) or modifying the existing carriers. I don't have the equipment needed to make the rings so I'd be looking for a local machine shop to do the work. But ultimately it seems that might start costing something close to the price of just getting new carriers. Unless I'm mistaking the amount of work involved?

Anyway, would love to hear any updates you have on the results of your mod.