Results 1 to 36 of 36
Like Tree2Likes
  • 1 Post By Dimal
  • 1 Post By TOK

Thread: BNZ MD74 conical burr grinder

  1. #1
    Senior Member
    Join Date
    Aug 2010
    Posts
    116

    BNZ MD74 conical burr grinder

    Gene Cafe Coffee Roaster $850 - Free Beans Free Freight
    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

  2. #2
    Mal Dimal's Avatar
    Join Date
    Oct 2004
    Location
    Warwick, QLD
    Posts
    16,994
    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 likes this.

  3. #3
    TOK
    TOK is offline
    Senior Member
    Join Date
    Apr 2013
    Posts
    697
    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.
    Dimal likes this.

  4. #4
    Site Sponsor coffee_machinist's Avatar
    Join Date
    Jun 2011
    Posts
    683
    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.

  5. #5
    Senior Member
    Join Date
    Oct 2007
    Posts
    791
    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!

  6. #6
    Senior Member
    Join Date
    Aug 2010
    Posts
    116
    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.

  7. #7
    Senior Member
    Join Date
    Aug 2010
    Posts
    116
    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?

  8. #8
    Site Sponsor coffee_machinist's Avatar
    Join Date
    Jun 2011
    Posts
    683
    Yes they can. The Faema MC is a BNZ MD74 in Faema clothing.

  9. #9
    Senior Member
    Join Date
    Aug 2010
    Posts
    116
    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

  10. #10
    Site Sponsor coffee_machinist's Avatar
    Join Date
    Jun 2011
    Posts
    683
    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.

  11. #11
    Junior Member simoto's Avatar
    Join Date
    Aug 2014
    Posts
    10
    Quote Originally Posted by coffee_machinist View Post
    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.
    uploadfromtaptalk1408098840072.jpg

    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.

  12. #12
    Junior Member simoto's Avatar
    Join Date
    Aug 2014
    Posts
    10
    Bump. I'm really hoping someone can lend some insight as to where I might find proper bnz Md74 burrs.

  13. #13
    Mal Dimal's Avatar
    Join Date
    Oct 2004
    Location
    Warwick, QLD
    Posts
    16,994
    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?
    Last edited by Dimal; 25th October 2014 at 03:20 PM.

  14. #14
    Senior Member
    Join Date
    Aug 2010
    Posts
    116
    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.

  15. #15
    Junior Member simoto's Avatar
    Join Date
    Aug 2014
    Posts
    10
    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.

    IMG_20140815_031507_20140815032908264(1).jpg

    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........"
    Last edited by simoto; 6th November 2014 at 05:39 AM.

  16. #16
    Senior Member
    Join Date
    Aug 2010
    Posts
    116
    Quote Originally Posted by simoto View Post
    ...........
    $500 USD to have Christopher at CWE ship 2 sets.........

    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.
    Wow. That's just massively disappointing, so I hope you're able to resolve this with CWE. If indeed the burrs from them are the same as the Faema MC99 burrs you bought previously, then they are the same as the ones I purchased new from a parts supplier in Europe; however I won't tell you what they cost me as it would just make you angrier. I haven't tried my spares yet as my original BNZ are still in great condition (I bought the spares to see how compatible they would be), but I will check to see if they have the same cut geometry that your photos above show, and I'll let you know.

    Did you try contacting BNZ in Italy directly to ask them about spares? If not, then out of interest I will try to call them and ask about suppliers and genuine (or at least original design) replacements.

    By the way, thanks for the great information regarding comparison of grind speed, performance, and temperature. I'm sure this will be very useful for other BNZ owners.

    I'll let you know if I have any luck with BNZ Italy.

    Cheers

  17. #17
    Junior Member simoto's Avatar
    Join Date
    Aug 2014
    Posts
    10
    Quote Originally Posted by Mouldy View Post

    Did you try contacting BNZ in Italy directly to ask them about spares? If not, then out of interest I will try to call them and ask about suppliers and genuine (or at least original design) replacements.

    By the way, thanks for the great information regarding comparison of grind speed, performance, and temperature. I'm sure this will be very useful for other BNZ owners.

    I'll let you know if I have any luck with BNZ Italy.

    Cheers

    Thanks Mouldy, I really appreciate the help. I'd be super curious to know how your burrs compare. I'd spend just about anything to get the burrs identical to my originals.

    So today my baristas are all having major problems with the espresso. I left the new burrs in last night, hoping they would...I don't know....magically get better? Maybe I was just too frustrated and it was 4am and my shop would soon be open. I love my BNZ (with stock burrs). Since I've owned it, its been nearly impossible to get channeling. I would say that 95% of the 2k kg of grounds its output have been fluffy consistent and free of clumps. With the new burrs in I have yet to pull a beautiful shot due to at least heavy clumping, probably uneven grind as well. I'm getting so much clumping its enraging. My Rancilio MD50 decaf grinder is producing a much better grind and shots.

    I will reinstall the original burrs tonight when we close, and hope that I can find an identical replacement soon, or I'll be biting the bullet, and purchasing a new grinder, something readily available locally. Probably a Mazzer Robur E, though I'm open to suggestions....

    I did email BNZ, but have yet to hear back

    So having the stock burrs out, I took some more precise measurements of the different blade cuts. Here is the same image with those measurements.

    bnz-vs-faema.jpg
    Last edited by simoto; 6th November 2014 at 12:42 PM.

  18. #18
    Senior Member
    Join Date
    Aug 2010
    Posts
    116
    Tonight I checked my original BNZ burrs for you against the Faema ones I bought. As you can see in the photo, they are different in the same way yours are. The measurements are basically the same as on each of your burrs.

    I will try to call BNZ Italy tonight to see if they can advise where the original design burrs can be bought or if they will sell direct. Will let you know.
    Cheers

    ImageUploadedByCoffeeSnobs1415271264.209519.jpg

  19. #19
    Junior Member simoto's Avatar
    Join Date
    Aug 2014
    Posts
    10
    Man that's too bad! Thank you for checking though! It's funny, all the photos of four hole 68mm conical burrs for sale at cafeparts.com match the cut of the original bnz burrs. I'm tempted to order a set of each. Would still be cheaper than a robur...

  20. #20
    Senior Member
    Join Date
    Aug 2010
    Posts
    116
    I called BNZ Italy tonight and after initially fumbling by in enough Italian to get my query across, was told to call back at a certain time to speak to one if their guys who speaks English. He advised its possible to buy direct from them the BNZ burrs and suggested to send an email. So I sent them your photo showing the measurements of the two different sets of burrs as I want to be sure that the new BNZ burrs do in fact match the old ones. I will let you know when I get their response. He did advise that CWE are their reseller in Australia, so I find it strange that the ones you got were not the same as the old. That's why I want to double check the dimensions of the ones direct from BNZ.

  21. #21
    Senior Member
    Join Date
    Mar 2012
    Posts
    1,275
    Quote Originally Posted by simoto View Post
    Man that's too bad! Thank you for checking though! It's funny, all the photos of four hole 68mm conical burrs for sale at cafeparts.com match the cut of the original bnz burrs. I'm tempted to order a set of each. Would still be cheaper than a robur...
    Photos on a Webb site can be a good guide, but I would never rely on them for technical confirmation of the product. Original manufacturers Product/part numbers are the only certain way....
    .......but beware of "revisions" also !

  22. #22
    Junior Member simoto's Avatar
    Join Date
    Aug 2014
    Posts
    10
    Quote Originally Posted by blend52 View Post
    Photos on a Webb site can be a good guide, but I would never rely on them for technical confirmation of the product. Original manufacturers Product/part numbers are the only certain way....
    .......but beware of "revisions" also !
    Yeah I wasn't completely serious, also they give the external and internal dimensions, so it's not hard to see none will fit. I suppose I was exaggerating to express the lengths I'd go to find the stock burrs. I do find it interesting that the photos depict the blade cuts that look identical, since the cuts go deep enough to actually cross into the mounting holes.

  23. #23
    Senior Member
    Join Date
    Aug 2010
    Posts
    116
    Hi Simoto, while I await the response from BNZ (see my last post above), I thought I'd ask if you followed up with CWE as to the difference in the burrs they supplied compared to the original BNZ burrs? Did they confirm that they burrs they resell for the MD74 are supplied by BNZ in Italy?

    Hopefully I will hear back from BNZ when they're back on the office in about 4 hours time or so. I've asked them to measure the burrs they have in stock and compare the dimensions to those in your photo.

  24. #24
    Junior Member simoto's Avatar
    Join Date
    Aug 2014
    Posts
    10
    Hey mouldy, Christopher at cwe told me that these are the burrs he is supplied for bnz, but he didn't specify whether they come directly from bnz.

    My fear is that maybe bnz used to make the burrs specifically for the Md74, but has since stopped producing them in order to save money, and now simply uses the faema Mc99 68mm conical burrs. Though I can't see the faema design doing anything to make up for the problems I'm encountering with the burrs. I'd imagine the performance difference I've recorded would transfer to any grinder they'd fit.
    Last edited by simoto; 8th November 2014 at 09:01 AM.

  25. #25
    Junior Member simoto's Avatar
    Join Date
    Aug 2014
    Posts
    10
    Ok so just got this from Christopher at CWE in response to whether the burrs come directly from bnz in Italy.

    "Hi Simon,


    Yea they are. All parts we stock for BNZ are directly supplied from BNZ Italy


    I'm awaiting a shipment to arrive from them within the next few weeks so I can take some pictures of the burrs in the grinder as well as ones supplied as parts.*


    Cheers"

  26. #26
    Senior Member
    Join Date
    Mar 2012
    Posts
    1,275
    Is it possible that your original burr set in the grinder was NOT an original BNZ set ??

  27. #27
    Junior Member simoto's Avatar
    Join Date
    Aug 2014
    Posts
    10
    Quote Originally Posted by blend52 View Post
    Is it possible that your original burr set in the grinder was NOT an original BNZ set ??
    It's unlikely, as mine was brand new in packaging. Also, maybe you didn't read, mouldy has compared his stock burrs to the replacements he bought, and found exactly the same differences. It would be very coincidental if both of our grinders came with the same not stock burrs.

  28. #28
    Senior Member
    Join Date
    Aug 2010
    Posts
    116
    Simoto, I received a response from BNZ Italy. They didn't really answer my question though, as all they advised is that the burrs CWE supply are "100 % compatible with BNZ grinders". They suggested that the differences in tooth geometry and cut depth "do not affect the grinder in any way"; which certainly is at odds to your testing.

    I responded specifically asking if the burrs currently supplied with new BNZ grinders are the same as what we are calling the original BNZ burrs, or whether they now supply the different type only. There was definitely wording in BNZ's email to confirm there is a difference, so I want to confirm if so and if the originals can be purchased.

    I note your comments about the replacement burrs and whether the issues you experienced would likely occur on any grinder (including Faema mc99). It's a good point and I don't know an answer. What else could cause the issues you describe when switching between burr sets? The reply from BNZ also suggested checking the capacitors, in that after a period of time they may degrade, but I would have thought this would only affect starting, and would not explain the differences you see when switching burr sets.

    I will advise any further response.

  29. #29
    Senior Member
    Join Date
    Mar 2012
    Posts
    1,275
    I guess it's not impossible that BNZ/Faema/ any other grinder or burr manufacturer could change the detail design of their burrs for some reason ,(performance, durability, cost, etc), and just drop the superceeded design, .......and maybe after a few years even forget why they had done it !
    This reminds me of an earlier thread on grind speeds..
    http://coffeesnobs.com.au/grinders/3...tml#post539155
    Last edited by blend52; 13th November 2014 at 09:51 AM.

  30. #30
    TOK
    TOK is offline
    Senior Member
    Join Date
    Apr 2013
    Posts
    697
    If the BNZ came with non factory standard grinding burrs, then the grinder is in reality, *not a BNZ* because almost its entire performance (certainly from the grind quality aspect) depends on those burrs....what is a grinder if not a set of burrs being spun up by a motor.

  31. #31
    Senior Member
    Join Date
    Aug 2010
    Posts
    116
    Quote Originally Posted by TOK View Post
    If the BNZ came with non factory standard grinding burrs, then the grinder is in reality, *not a BNZ* because almost its entire performance (certainly from the grind quality aspect) depends on those burrs....what is a grinder if not a set of burrs being spun up by a motor.
    The grinders in question came with factory BNZ burrs; which perform brilliantly. The observation from at least two different users (I'm one of them) has been that replacement burrs from CWE and other suppliers of burrs for BNZ, are slightly different (in tooth geometry) to the ones originally fitted. In Simoto's case (see earlier posts), the replacement burrs resulted in noticeably slower grind rates and noticeably increased temperature of grinds, together with clumping. We are trying to understand if burrs the same as the original factory burrs are available. BNZ has been contacted and I'm awaiting their response.

  32. #32
    Senior Member
    Join Date
    Feb 2010
    Posts
    226
    "and I'm awaiting their response".
    As we (other BNZ owners) on the sidelines are.

  33. #33
    Junior Member
    Join Date
    Nov 2014
    Posts
    13
    Anyone tried the compak k-10 burrs?

    Oh and differnet grinders spin at different speeds, so burrs can behave very differently in different grinders. The faema may spin much faster.

    As for BNZ saying to check the capacitors, I also doubt this could be the issue as you wouldnt get such performance with the original burrs if there was a problem with a capacitor. Although Mouldy if there is a run capacitor aswell as a start capacitor, then a degraded run capacitor could be what they are referring too. Which would indeed affect the running of the motor.
    Last edited by Perfect; 2nd December 2014 at 03:48 AM. Reason: Response too short.

  34. #34
    Senior Member
    Join Date
    Aug 2010
    Posts
    116
    Quote Originally Posted by simoto View Post
    Ok so just got this from Christopher at CWE in response to whether the burrs come directly from bnz in Italy.

    "Hi Simon,


    Yea they are. All parts we stock for BNZ are directly supplied from BNZ Italy


    I'm awaiting a shipment to arrive from them within the next few weeks so I can take some pictures of the burrs in the grinder as well as ones supplied as parts.*


    Cheers"
    Hi Simoto,
    Have you heard from CWE in regards to if burrs in the new grinders are the same as the ones supplied as parts?

    I've not received any further response from BNZ on my questions explained in above posts. I may need to call Italy again to chase up a response.

  35. #35
    Junior Member
    Join Date
    Apr 2013
    Posts
    1
    Sorry to resurrect a very old thread, but was this ever resolved? The reason I ask is that I've just fitted a new set of what I believe are Italmill burrs to a Rossi MC with precisely the same result - they are very slow - and the cut matches the "bad" ones above. The ones I took out look like the older "good" ones. So this is not specific to BNZ. If you look on the Italmill site then all these 68mm grinders are specified with basically the same burrs, so I wonder what is going on. If you look at pictures of the OE pharos burrs then they also appear to be the new shape ones.

  36. #36
    Junior Member simoto's Avatar
    Join Date
    Aug 2014
    Posts
    10
    Quote Originally Posted by GlennV View Post
    Sorry to resurrect a very old thread, but was this ever resolved? The reason I ask is that I've just fitted a new set of what I believe are Italmill burrs to a Rossi MC with precisely the same result - they are very slow - and the cut matches the "bad" ones above. The ones I took out look like the older "good" ones. So this is not specific to BNZ. If you look on the Italmill site then all these 68mm grinders are specified with basically the same burrs, so I wonder what is going on. If you look at pictures of the OE pharos burrs then they also appear to be the new shape ones.
    I was never able to find a matching set to the stock bnz burrs. It essentially made my $2700 grinder that I relied on for my business, a worthless pos. It's really hard to trust companies when they just change such an important part of their grinder with no regard to the loss of quality and performance. I bought a mazzer robur e. My 3 year old bnz is a paperweight.

    My guess is these burrs seem to be used in several brands and models of grinders, and they're probably produced by a third party for all of them, so they may have no control over the design. These kind of limitations will keep these companies from ever becoming mainstream. No one in the US has heard of bnz, and at this point I wish I hadn't either, I'd have bought the robur straight off.



Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •