Mazzer Super Jolly Duranium Burrs at GreatInfusions - Page 3

[DigMe]

No.

I've never heard of that.

I've seen reports of it a couple of times on the forum. It's the reason for making sure the grinder is running when adjusting to a finer grind from what I've always understood.

brad

[DigMe]

What's "wrong" with stock OEM Mazzer burrs? What does the Duranium propose to improve on (and if it isn't flavor I'm not interested and if its just burr life is this really and issue for home use)?

One thing that Dan said about them but that I don't believe he would like entered for the record as any kind of hard comparison is:

It may be my imagination, but in addition to being really really fast, the taste profile seems different. A lot more chocolates, almost to the point of tasting like a tight ristretto despite my usual brew ratio.

he went on to say:

My preliminary thoughts on the early extractions with the Duraniums: If you're a latte lover who craves bass notes and chocolates, it may be worth checking into these space age burrs next time you change them. That said, it wasn't a blind taste test and thus my comments should be given appropriate weight (read: near zero )

He also noted the stalls in that same thread.

brad

[Jasonian]

Jason, I've got no idea what this will tell you, but anything for the good of the cause.
<image>

Sorry about the quality, it's the closest I can get with the zoom lens that came with my Canon dSLR. If you'd care to donate a nice macro lens and lighting system, I promise to do better.

Thanks a lot, Jon.

It doesn't do good on its own, but report of "fluffier grounds" got me curious.

[Jasonian]

Titanium, molybdenum and stainless steel alloy?

http://coffeegeek.com/forums/espr...ders/353175#353175

[RapidCoffee]

3 week update on the new Mazzer Super Jolly Duranium burrs

I observed three incidents of grinder stalling in the first week after installing the new Duranium burrs. Each stall was associated with grinding a relatively light home roast (a la Paradise Espresso Classico). Turning on the grinder produced a hum, but the burrs did not start spinning. Immediately switching the grinder off and turning it back on allowed the grinder to function normally.

I'm happy to report no further incidents of grinder stalling since the first week. The stalling may have been caused by the brand new burr cutting edges, now dulled enough to reduce the required startup torque sufficiently to eliminate the problem. One hopes.

Aside from the initial stalling issue, I really like these new Duranium burrs. They grind 50-100% faster than the standard Mazzer burr set, should have significantly greater longevity, and produce a grind that seems very similar to the standard burr set. If another couple of weeks go by without problems, I'll give the Duranium burr set a cautious thumbs up. With one major caveat: grinder stalling is a real issue, especially with lighter roasts, until the burrs get broken in.

[TimEggers]

Thanks for the follow up John I look forward to further reports.

[RapidCoffee]

7 week update on the new Mazzer Super Jolly Duranium burrs

During the four weeks since my last post, I observed one more case of grinder stalling with the Duranium burrs. In this latest incident, I was grinding some smallish Yemen beans, and the cause of stalling was obvious. A peaberry bean was wedged between the burrs, preventing them from rotating on startup. Dislodging the bean allowed the grinder to function normally again. (Shoulda taken a pic... )

Anyway, that tears it. I can no longer recommend these burrs, due to ongoing stalling issues. It's a shame, really: the very people who would benefit most from the increased speed and longevity of this new burr set are also the ones most likely to suffer ill consequences from grinder stalling. I'm referring to busy coffee shops, where a barista won't always notice a stalled grinder immediately. That's asking for trouble.

BTW, I plan to keep the Duranium burrs installed on my Super Jolly. For a home barista, the infrequent stalls are easy to catch if you grind per shot. Aside from stalling, I really do like the new burr set.

[Psyd]

Anyway, that tears it. I can no longer recommend these burrs, due to ongoing stalling issues.

So, would you guess that if they were installed in a Major with an 83mm diameter, the stalling would still be an issue, or would the Major's horsepower make it moot? I'm still willing to test a set or two, if someone's interested in making Major burrs...HINT, friggin' HINT! ; >

[mteahan]

We have had little feedback so far on the Duramills stalling save a couple of reports in the forums online. We haven't heard of any issues on the European side, so I think I have a handle on what might be happening. Especially when you consider that it is not a consistent problem.

Motors that operate on 60 hertz have slightly less torque than those at 50 hertz. We had this problem on the gear drive mechanisms of first generation super automatics. The same machine the operated at 12 RPM in the European Union had to be geared down to 10 RPM for the US at the same voltage rating. It did not have the torque to prevent the occasional jam.

Additionally, all of the torque to start the motor comes from the capacitor, which discharges almost immediately after the start cycle. If it isn't able to discharge enough to start the motor, the run windings of the motor will not be able to do it. Three phase motors are able to provide continuous torque and would eventually power through the bean.

The aggressive cut of these mills is rather like starting your car in second gear; it sounds like some motors may be at the cusp of the torque needed to perform effectively. It can be especially interesting if the line voltage gets closer to 110 than 119 volts. Some coffee bars and home users will never encounter a problem.

We may be able to manipulate the microfarad ratings of the cap to increase starting torque. Doing so can drop the run voltage very slightly, but shouldn't pose any long term problem. Those that grind to order can also use the Heather System: use the closing gate of the hopper to feed the beans. The extremely high end commercial grinders use lasers to measure the distance between the mills and start and stop with zero coffee load.

It appears that these mills push the design limits of some grinders. Ironically, we have a set installed in the Chinese Mazzer knockoff over at Supreme Bean and they have reported smooth sailing. I would hate to think they are using a tougher motor assembly than Mazzer. There might be a run on these things, even if they are a little goofy looking.

We have not brought in the Duramill for the Major yet. Large diameter mills use much larger motors but also run at lower RPM and require more starting torque. The speed at the outer edge of the mill (mm per second) is critical to grind quality. Smaller mills can spin faster than larger ones and not burn the coffee. The elongated cut pattern of conical mills allows for further reducing the speed, but requires gear reduction to overcome the torque issues.

We are following the progress to see how things pan out.

Michael Teahan
Espresso Resource / Espresso Part Source

[RapidCoffee]

The aggressive cut of these mills is rather like starting your car in second gear; it sounds like some motors may be at the cusp of the torque needed to perform effectively.

Excellent analogy. There are no stalling issues once the burrs start spinning.

We may be able to manipulate the microfarad ratings of the cap to increase starting torque.

If you're referring to the startup capacitor, I had the same thought. Knowledgeable sources suggested this was unlikely, but perhaps it was a reasonable idea after all...

Thanks for chiming in on this thread. I hope to hear more as these burrs see wider distribution. Other than Dan's initial tests, I seem to be the only home barista posting reports on this site.

[Psyd]

Other than Dan's initial tests, I seem to be the only home barista posting reports on this site.

I'd be happy to put a pair in one of my Majors, as I've continuously pointed out (; > ) to have a side-by-side HB comparison, and begin contributing the moment that Major burrs become available.
I do think that taking note that the cut of the burr is more aggressive, and may, occasionally, require a second attempt at starting the grinder, wouldn't be a great huge deterrent for me.

[Gugies1]

Hi All,
This is my first post on H-B, so let me start off by saying hi! First off let me get the conflict of interest stuff out of the way, I am both a home barista and also work at Barefoot Coffee Roasters in sales and wrench turning, both myself and BCR for buy products from Great Infusions.

That being said, I originally bought a set of these burrs intending to use them on my home super jolly but i already had new burrs on my home unit and one of the super jollys at BCR was due for a burr change. So i threw them on it instead. Hot Damn! When i started the thing up it I couldn't dose fast enough. I did have a handful of times where the burrs stalled. But after a little while that went away. The baristi put a load of coffee through our grinders, far more then a home user ever would (if you are, apply for a job) so i was really interested in seeing how the burrs would fare wear wise... After 4 months the Duranium burrs still are rockets.

We actually almost used the Duranium SJ for WRBC this year... We had a loaner robur show up in the mail unexpectedly.

So in recap: on our bar, i heart duranium.

[Psyd]

This is my first post on H-B, so let me start off by saying hi!
We had a loaner robur show up in the mail unexpectedly.

Hi Scott. If the baristi I met and the coffee I drank are any indication of what a BCR barista/wrench's opinion is worth, then pay close attention, Those folk impressed me muchly.
A Robur show up in the mail unexpectedly... yeah. One of these days I hope to utter such a phrase... ; >

[ebprod]

I think I saw that these burrs could be used in a Mini-E. Is that correct? Would that grinder be up to the task?

Thanks.

-Joe

[HB]

Would that grinder be up to the task?

I never tried, but I doubt it. The Mini E's motor is listed as 250W versus the Jolly's 350W. Given the reports of occasional stalling with the Super Jolly, I assume the problem would be worse for the Mini E (corrections welcome).

[Randy G.]

Hi All,
This is my first post on H-B, so let me start off by saying hi!

Welcome, Scott!

I had the pleasure to watch Scott pour latte art at Great Infusions a month or two ago.. I learned a TON from watching him! [I wrote a review of the visit as well as a "How To" article on steaming milk and pouring latte art, much of it based on what I learned from watching you. They are on my website.].

Please hang around as you have a ton of valuable info to share!

[serenewu]

I received Duranium yesterday. I believed every home barista are interested in this burrs like me because the blind test of the burrs beat Kony. So, I wanted to join this thread to give you some updates about this new burrs. First thing I did after I received them is to measure them. It's a very interesting result. I used digital scale (this scale was to measure diamond).
One burr is 90.0g, the other is 90.3g, a little different in weight. I measured the original burrs from my Super jolly, both of them are 87.8g. I owned my super jolly for two years. If they have some weight different, I can understand. But their weight still the same, and the brand new Duranium burrs have a little weight different. I want to ask others owners, did anyone of you notice the weight different situation?
Before I ask GreatInfusions I want to hear your option. Meanwhile, you may be interested know, I come from Taiwan. Before I came to US, I had been using the Taiwan's made "Super jolly" or Chinese Mazzer fore several years. It has very high quality and the price is only 1/2 less than Super Jolly.
Michael mention those new burrs worked well on those "Chinese Mazzer". Because the Chinese Mazzer may use better tougher motor. I can tell you this model motor provide 1/2 HP. But in Taiwan, there are two other models of grinders (all made in Taiwan, build from Super Jolly model) and the only difference is the burrs. The expensive one using super jolly burrs and other model using Taiwan made burrs. I observed occasional stalling problem in cheaper Taiwan-made grinder. Every time it happens, it send message to that me I need to clean the grinder. Basically, I made 5 shots for adjusting new burrs, today. I didn't have any stalling situation.
I will keep updating here.

[HB]

I want to ask others owners, did anyone of you notice the weight different situation?

Sorry, I did not weigh the Duraniums. I have an old set of 58mm burrs and just weighed them: 70.5 grams versus 70.3 grams. Oh well, despite the 0.2 gram difference in weight, they served me well for years.

[espressme]

FWW,YMMV
I am happy to say that my well used ancient model Mazzer SJ (doser removed) took to the Duranium burrs with a passion. The first grind was clumped. After that, I have found the grind to be fluffy and unbelievably consistent. There may be a change in the taste profile and when I get back to a roast that I am more familiar with, I shall be better able to judge.
Already, I know that I would not go back to the steel burrs. These will probably last the rest of my life and be passed on!
I would suggest Duranium to anyone buying a used machine or wanting to replace burrs.
Cheers
Richard / espressme
PS Notice in a post above that a new Capacitor could be needed to correct for a stalling at startup. Mine did not need it.

[RapidCoffee]

I received Duranium yesterday. I believed every home barista are interested in this burrs like me because the blind test of the burrs beat Kony.

I was unaware of this blind test (in fact, I'm unaware of any bona fide blind testing of any grinders ), and would be very interested in learning the details. Where did you hear about it, and how was it designed? Has anyone performed blind testing to compare standard vs. Duranium burrsets on the SJ?

So, I wanted to join this thread to give you some updates about this new burrs. First thing I did after I received them is to measure them. It's a very interesting result. I used digital scale (this scale was to measure diamond).
One burr is 90.0g, the other is 90.3g, a little different in weight. I measured the original burrs from my Super jolly, both of them are 87.8g. I owned my super jolly for two years. If they have some weight different, I can understand. But their weight still the same, and the brand new Duranium burrs have a little weight different. I want to ask others owners, did anyone of you notice the weight different situation?

Sorry, I didn't think to weigh the new burrs. Next time I clean the grinder, I'll pull the top burr off and weigh it. My old SJ burrs weigh 89.0g and 88.9g (virtually identical on a 0.1g resolution scale). That's only 1g less than your Duranium burr weights. IIRC, the new burrs were a bit taller than the old ones, and as a result, my SJ grind setting is slightly coarser than it used to be.

... I have found the grind to be fluffy and unbelievably consistent. There may be a change in the taste profile and when I get back to a roast that I am more familiar with, I shall be better able to judge.
Already, I know that I would not go back to the steel burrs. These will probably last the rest of my life and be passed on!
I would suggest Duranium to anyone buying a used machine or wanting to replace burrs.

I've had the Duranium burr on my SJ for over 3 months, and have no intention of going back to the standard burrset. The stalling issues went away after the first month. I only had a handful of stalling incidents, mostly associated with small beans wedged between the burrs. If you tighten the grind setting while the grinder is off, this definitely increases the chance of a stall. Nonetheless, stalling is a real issue with these new burrs, so be careful, at least during the first few weeks.