BNZ MD74 conical burr grinder

[Mouldy]

Hi all,

I have a BNZ MD74 that was included as a freebie in the purchase of a used machine. It appears in perfect condition and I don't think it has had much use. I'm wondering whether to sell it or use it to replace the Cimbali Jr grinder I'm currently using. There doesn't appear to much info around on the BNZ, but I can say it is built like a tank and very easy to strip and clean. Would love to hear from anyone who has used an MD74 and if any advice on if I should switch from the Cimbali. Would also like to know if the BNZ burrs are common with any other units, or where they can be sourced from.
Cheers

[Dimal]

G'day Mouldy...

BNZ grinders are right up there with the best in the market for quality and engineering. There are a few CSers who have them at home and I'm sure replacement burr-sets can be obtained reasonably easily as plenty of cafes have them on their counter-tops too. The Cimbali is a pretty decent grinder too of course and I guess the only way to make a decision on which one to keep, is to try them side-by-side with identical coffee and try to identify any differences on the palate. That'd be what I would do anyway...

Mal.

[TOK]

The only other thing I would add is to run the BNZ for a little while and become familiar with the modus operandi. An individual can then decide whether he finds one grinder easier to use or "live with" than the other, and a choice on which one to keep can then be made.

[coffee_machinist]

BNZ is a great grinder, the doser in particular found favour with the WBC crowd for many years. Very nice action and clean sweeping when properly maintained. One thing to do if you're up for tinkering would be to disable the auto-stop and remove the switch so you can sweep out the throat - it holds alot of coffee.

[roknee]

ive done exactly that mod CM and fine it a nice grinder for home albeit large. fits under my cupboards by mms, with no hopper lid.
great doser and nice coffee drop. pretty sure coffeeparts do spare bur sets. nice gift!

[Mouldy]

Thanks for the responses.
Regarding the mod to allow sweeping of the throat, can you advise what is involved? Is it a case of removing the paddle that hits the microswitch so the throat can be accessed via the dosing chamber lid?
Thanks.

[Mouldy]

Wondering if anyone knows if the conical burrs of the BNZ MD74 are common with any other grinders? Specifically, from what I can find, the 68mm Faema MC burrs appear identical in regards to key dimensions, rotation direction, and bolt pattern, but wondering if anyone knows if they can be used in the BNZ?

[coffee_machinist]

Yes they can. The Faema MC is a BNZ MD74 in Faema clothing.

[Mouldy]

Great thanks for reply. I was keen to understand as i can buy the Faema MC burr set for a song compared to what I've found for those sold for the BNZ. By the way CM, can you explain the throat mod you mentioned in your other post in this thread? Cheers

[coffee_machinist]

Basically there will be a lot of coffee hiding behind the auto-stop switch, these have a very capacious throat. All that's necessary is safely taking the normally closed doser switch out of the circuit (and by safely I don't mean stripping back some wire, twisting the ends together, garnishing with electrical tape, shoving the leads out of sight and hoping for the best - I've seen it done and it's nearly got me zapped), and removing the ancillary plakky bits.

Depending on your confidence with 240v and basic circuits, proceed with caution or contact a tech, which is always my advice.

[simoto]

Yes they can. The Faema MC is a BNZ MD74 in Faema clothing.

So I was very excited to read this, as I've been having no luck finding new burrs for my bnz Md 74 here in the US. Almost no one has heard of it here. So I went ahead and ordered the 68mm conical burrs for the faema and they certainly looked identical at first glance.

Though once installed, and operational, it was grinding much much slower. No problem with rotation speed, it just wasn't pulling beans in at the proper rate. It was probably taking about 10 seconds to grind 20g, which would have previously taken 3-4 seconds with the stock burrs.

So I took the burrs out and compared them very closely to the original bnz burrs. They are in fact visibly different.


Put the old burrs back in and its back to the Super fast grinder I rely on in my cafe. Sure would like to get the proper burrs though as I've probably ground 1200 pounds through these burrs.

[simoto]

Bump. I'm really hoping someone can lend some insight as to where I might find proper bnz Md74 burrs.

[Dimal]

Pretty sure Coffee Works Express in Sydney carry BNZ Grinders and most likely will have burr-sets on hand for them...

Google them and see how you go...

Mal.

Oops, sorry. Didn't realise "simoto" resided in the States.
Perhaps someone could acquire a new burr-set for you from here in Oz and send them to you?

[Mouldy]

Sorry simoto, I can point you in the direction of where to buy in Australia, but that's not much use if you're in the US.

You could try asking BNZ in Italy to advise their distributors in the US, or if they will sell you directly and post.

Contact them here:
http://www.bnzgrinders.com/index.php...id=1&Itemid=10

Good luck, and perhaps post back if you have any luck.

[simoto]

Hey fellas, thanks for responding! I actually got in contact with the parts guy at Coffee Works Express, who after explaining my situation, informed me that in fact the BNZ conical burrs are a different cut than the Faema MC99, and he had them in stock.

I own a pretty busy coffee shop here in Portland, OR, and have been getting pretty desperate for new burrs. We grind about 6kg a day in my BNZ, open 7 days a week, meaning these burrs have seen about 2k kg in the year I've owned it. They are still in ok shape, but I'm beginning to notice an occasional clump or two, which is something this grinder has almost never done. I have modified it to be doserless with a stainless cone meant for a mazzer mini E. I believe I got the idea from this forum.

Anyway I wanted to explain my position before I admitted to spending about $500 USD to have Christopher at CWE ship 2 sets. I also got an extra hopper, since I had wanted one, and shipping was going to be about 170 either way.

So I received the burrs and guess what. They are exactly the same cut as the faema mc99 burrs I got here in the states for $90. It took a few beers not to throw a fit. So now I have 3 sets of burrs that "fit" and "function" but at a pretty steep cost to the quality and speed of the grounds.

Here is a comparison of the stock bnz burrs I know and love, and the faema mc99/ cwe bnz md74 that seem to be the only replacements available now.



I have been in contact with Christopher at CWE and he asked me to try them out and keep him updated on my results. Here is what I sent to him after a brief testing period.

"....With the stock burrs I get 18-21 grams in about 3-4 seconds(tested this tonight), and it heats the grounds very little. With an ambient temperature of 72 degrees Fahrenheit, the grounds reach about 78 after grinding 100g.

Now tonight I've put in the burrs you sent me and ground about 6kg to "season" the burrs hoping they would improve. I waited about 20 minutes before testing, to let it cool down.

My results are, about 20g in 10 seconds, and a very toasty 101 degrees Fahrenheit after grinding 100g. Also, probably due to the heat, I'm getting quite a lot of clumping, which has never been an issue with this grinder. I understand your comment about how grinding slower can reduce heat, though that should be more dependent on rpm, which is quite low on the md74, however because the blades are cut shallower, I believe the problem is that beans are unable to fall in at the correct rate, and spend more time in contact with the burrs, and heat up........"