As any of you who have tried to take apart a mazzer doser (Dan included) know, the lower vane is probably the hardest part to take off on the mazzer Doser.
After removing the doser from the body, and removing the bottom piece (with the thwacker):

The first step is simple, knock out the pin that keeps the bolt from spinning.

The next step is where most people (including myself at first) go wrong. Since the bolt is screwed in the lower doser vane, you need to hold the lower vane and turn the bolt with a 12mm socket.

The first thought that comes to mind is to stick something into the hole where the grinds fall, to keep the vane from spinning, while applying superhuman strength to the ratchet connected to the bolt.

The problem is that these vanes are designed to sweep coffee into a hole, not to hold 200+lbs of force.

AND THEY BREAK! They are not cheap to replace either!!

So here is the proper way to remove it (with 0 chance of breakage ZERO!!)

Step 1: Take pliers (long needle nose work great) and hold the golden gear and the inside wall of the dispensing chute:


Here is a better view:


NOTE: YOU ARE NOT HOLDING THE VANES!

And then ratchet away:


With this technique, you are holding the golden gear from spinning and not the vanes, so there is no pressure on the vanes. The golden gear is quite thick and will definitely not break.

Enjoy... Now you guys have no excuse not the deep clean your mazzer... believe me there is a lot of stuff there!

Full Disassembly guide here: http://www.monkeyfaq.com/mazzer

Thanks! This is a great post. I got lucky when I took mine apart and did not break a vane, but I will be using this hint next time.

Take Care,
Dan

I could have REALLY used this like,, 3 days earlier.

My lower star, has two remaining vanes lol. As im trying to turn the gear im like "whats that sound? Hmm.. wrench musta slipped." NOPE! That would be (surprisingly) weak vanes poppin right off.

So.. An electric tape mod and a few tears, and the doser works just fine.

funny thing.. after two hours of breaking down the doser..Ive decided to go doserless, as my thwacker is stiffer then Id like, even after cleaning it all out. Seems I thought it would be loose, like a Rocky or an MDF...(or do I need a new spring?)

this just got bookmarked, though. I always like when people do things like this, just cuz. Good job!

Jeff

Hi guys,

been there done that (broke a vane):)

It's a bit funny as I thought it went quite easy, I put some force into it and it let go. Turned out it was one of the vanes that broke, not the screw that let go.

I did a similar trick, but instead of using pliers I stuck a small screw between the gear and one of the walls. It took so much force that it actually bent the screw and crashed its threads:O It was an old doser though, so I wasn't surprised (I almost broke my arm when trying to unscrew it).

Regards,
dsc.

I also broke a vane, but my Mini is happily humming along without it

Ilya's disassembly guide is very helpful, but I do not recommend the above method for removing the lower vane of the doser. Not without reservations. I tried it on my Super Jolly and the bolt on the golden gear is too tight. The metal of the dispensing chute is soft, and I felt it begin to fail while I was pushing on the socket wrench. Yes, I was going the right way; yes, I'd removed the pin. That bolt is just too tight. I slightly distorted and cracked the bit of the dispensing chute that was in the plier grips. It's not the end of the world but I'm glad I stopped before going any further.

If you use this method I recommend not putting too much steam behind it. I wound up not taking mine apart. It was only a cleaning so no big deal.

@nostick:

are you sure you are doing it right?

I have disassembled 7 mazzer grinders using this technique and have had 100% success on each using the technique described above.

(I only broke one using the hammer in the grind chute pictured here: http://www.monkeyfaq.com/mazzer/doser.html) but luckily had a spare


Are you sure you are gripping very tightly with the pliers? maybe try having one person hold the pliers while you twist the bolt? I am surprised that yours is stuck sooo tight. I have had some that were very tight, where I needed to get a helper to hold the pliers for me, but this method works 100% of the time.

If your bolt is still stuck after the two-person method.. then try soaking it in WD-40 or something similar (you'll need to clean it well after though because wd-40 is clearly not food safe)

This was very helpful, thanks.
As i cranked away with my socket wrench i wondered why they tighten it down with a gorilla. When i reassembled it i just snugged it nicely.

I also broke my chute using this method- I think the trick is self locking pliers that allow for no "twist" as you crank. VERY soft metal.