Burr Life

[wattgn]

This is an interesting topic as it seems to me that most people grossly under-estimate the lifespan of the burrs.

My coffee usage is say 40 x 365 grams. Say about 15kg per year. The burrs are rated, I have heard for about 600kg of coffee. The grinder is 10 years old or thereabouts. It has therefore had about 150kg of beans through it which means the burrs are 25% worn.

I stripped it down and looked at the burrs a few days ago and cleaned everything. Looks good. I wouldn't replace the burrs based on espresso, these estimates or what I could see.

A commercial grinder with flat burrs will do usually 800kg of beans. In a cafe, let me guess. Say 10 grinds per hour of 20g is probably a reasonable estimate for a day over say 10 hours. 2kg per day or 720kg per year so burrs will need replacing every year.

I wonder how many people objectively consider this as CSers are always talking about replacing burrs. I would think unless your beans have nuts and bolts in them that it is unnecessary for most people to EVER change the burrs in the lifetime of a home grinder.

[AlMac]

I replaced my Mazzer Mini burrs after 11 years.
Probably could have done it at 8-9 years though.
Difference is noticed in shot quality and in the pour from the naked PF.

Gearing up for my next burr change in 2022.

[wattgn]

I replaced my Mazzer Mini burrs after 11 years.
Probably could have done it at 8-9 years though.
Difference is noticed in shot quality and in the pour from the naked PF.

Gearing up for my next burr change in 2022.

I think you brought the Mazzer around to my place? I remember a Mazzer. Nice grinder, quiet compared to the Rocky.

I've got my first burr change down for 2046, provided I'm not dead by then...)

[TampIt]

I replaced my Mazzer Mini burrs after 11 years.
Probably could have done it at 8-9 years though.
Difference is noticed in shot quality and in the pour from the naked PF.

Gearing up for my next burr change in 2022.

I often tell people that a commercial grinder may keep spinning the burrs for years, however the quality in the cup drops "whenever the burrs are worn" - whatever that means.

Unless you have a stray microscope, even reasonably good looking burrs (using the naked eye) are often well past their best.

That is why you will see such wildly differing view within CS as to burr life.

I tell my friends to check every three to four years against a new comparable grinder - if the new one is a better cuppa, either replace the burrs or upgrade the grinder.

TampIt

[TampIt]

I replaced my Mazzer Mini burrs after 11 years.
Probably could have done it at 8-9 years though.
Difference is noticed in shot quality and in the pour from the naked PF.

Gearing up for my next burr change in 2022.

I often tell people that a commercial grinder may keep spinning the burrs for years, however the quality in the cup drops "whenever the burrs are worn" - whatever that means.

Unless you have a stray microscope, even reasonably good looking burrs (using the naked eye) are often well past their best.

That is why you will see such wildly differing view within CS as to burr life.

I tell my friends to check every three to four years against a new comparable grinder - if the new one is a better cuppa, either replace the burrs or upgrade the grinder.

TampIt

[wattgn]

The Mazzer Mini has 58mm burrs and 300kg is the recommended life of the burrs from what I can find about 600 pounds or so.

The Rocky has 50mm burrs but I found only one second hand guess of 75 - 100 lbs which is say 40kg. It makes no sense of course why it should be that much less but unless the manufacturer publishes something it is just somebody's guess.

I'm sure the time to change them is when you aren't happy any more with the grind. It is certainly cheaper to spend $50 on new burrs and an hour of hour time to change them than buying a new grinder.

It is also possible of course to damage them with foreign matter in your beans such as stones.

I think after reading a bit more, I'm thinking opinions vary hugely, and hard data and recommendations on the lifespan of the burrs is often not put out by manufacturers except for the true commercial grinders, where this information is necessary for the running of your business. Commercial grinders often require burr changes only after 800kg of beans.

[wattgn]

This link is worth looking at too http://coffeesnobs.com.au/grinders/3...h-quality.html.

The poor quality rough edges on some burrs mean some quantity of beans or even rice is required before they grind properly.

This link on changing burrs and burr life of some grinders.

http://www.genovese.com.au/is-it-tim...grinder-burrs/

[acid_rider]

so conservatively speaking, how many kg of beans are Rancilio Rocky grinder burrs are good for??
(min-max) ?

[wattgn]

so conservatively speaking, how many kg of beans are Rancilio Rocky grinder burrs are good for??
(min-max) ?

Burr life is rated mainly for commercial grinders as it has a financial cost. The Mazzer Robur has slow moving large conical burrs that last for 850kg.

The Mazzer Mini with 58mm burrs last for 300kg.

I doubt if the Rocky burrs would last for much less. Most are used in homes so I doubt if they ever wear out. It is easy and cheap enough to replace them but if there is no issue withthe coffee then it almost seems pointless to replace them.

[woodenteapot]

This link is worth looking at too http://coffeesnobs.com.au/grinders/3...h-quality.html.

The poor quality rough edges on some burrs mean some quantity of beans or even rice is required before they grind properly.

This link on changing burrs and burr life of some grinders.

Is it time to change your grinder burrs? - Genovese Coffee

Thanks for the links! I've been using a pre-loved ex-cafe Mazzer Major for the past year and finally decided to spend money to change the burrs yesterday. Absolutely amazed at the difference - single dosing 18g of coffee used to take close to 30secs, now it takes less than 10secs.

Used about 1kg of old stale beans to try to run the burrs in before making shots, still haven't had enough time to make coffees to taste the difference.

Going by the above link though, Mazzer Major burrs rated for 600kg of coffee means if my current use stays the same, I'll only have to change the burrs in 38 years time.