Fiorenzato Mestre T80 - Remove Burrs (Help!)

[Onneb]

Hi,


I recently picked up a used Fiorenzato grinder (Mestre T80 - unconfirmed) in need of a good cleaning but I can't seem to remove the adjustment collar to get to the burrs.


I have tried winding it toward the the coarser grind (clockwise) to try and unscrew it completely. but it seizes after several rotations and is extremely hard to move beyond a certain point.

I thought perhaps there was an adjustment screw i needed to remove, but I can't see one.


I have read that it may be seizing due to residue locking the thread, and that a soak in a cleaning solution may loosen this thread (tsp cleaner in one case).


Questions:


1. Is continuing to unscrew the adjustment collar the correct thing to do? Or am I going to damage something?


2. If a soak in a cleaning solution is required, is TSP cleaner a wise choice for cleaning these metal components?

 

[shadow745]

When you do get it to turn is it smooth? Does the burr carrier/collar appear to be level? I ask as I would hope it wasn't cross threaded.

Could just be severely gummed up. I recently bought a Rocky that was hardly used, but sat for years with molded coffee tar gunking up the threads/burrs. Had no issues removing the burr carrier though.

Regarding soaking... is the entire assembly removable for soaking or how have others accomplished this?

 

[Musicphan]

I would look for a safety screw.. some grinders do have one. But most likely its coffee oil junk/glue. As shadow was asking - if it turns smoothly then you don't have a threading issue. I was shocked when I rebuilt a Bunn G3.. I had to use a blowtorch and impact screwdriver to get the burr threads off. (obviously not related to your problem)... I will never underestimate oil buildup.

 

[solock]

I have 2 t80's, a doser and a doserless, and they both exhibit the same issue, the very sharp threads pack in the coffee residue and are really tough to unscrew the upper burr carrier. I then meticulously clean the threads with a toothpick and it is good for a while like maybe 2 months or so. If i were smart I'd clean it more often but it is a tertiary grinder at best for me and it doesnt get the love it deserves. I found that a turn till it gets snug, back off and try again. For me this is the normal for this grinder as both of mine do it.

 

[Onneb]

Thanks for your help guys!

I did manage to get it off.

Turns out the T-80 has no safety screw. As mentioned above my issue was with coffee residue build up inside the thread of the adjustment collar. I used WD40 lightly sprayed into the small gap visible between the underside of the adjustment collar and the body of the grinder. Initially the brass thread was just visible, and i spun it back and forth and slowly worked it off. I had someone to help hold the machine still and the latch open while I twisted, it still required a significant bit of force.

While I was cleaning I took care to clean the thread properly and can also recommend the use of a toothpick to run around inside the thread the clean it. What I removed were long strands of hardened coffee residue, no wonder it was near impossible to unscrew.



Cleaning the grinder in general was a real lesson in not underestimating oily coffee residue. I ruined 3 sponges trying to removed build up from the machine. It is next level stuff, it's incredibly tacky, hot soapy water barely gets it moving once it's old and hard enough. If anyone has had more luck with a more powerful cleaning product I'd be interested to know.

My final piece of advice is that the hex head set screw that holds the lower blade cradle to the motors drive shaft has a left handed thread! I wouldn't recommend removing it anyway, the body assembly seems to be pressed together so you won't get much further disassembling the body once you have it off, and there wasn't much residue build up under there. BUT if you must, I'd recommend locking the cradle by inserting something (screwdriver) in the coffee outlet hole to stop the cradle rotating, then undo the bolt with the correct reverse rotation!

As you might have guessed, I sheared the head off the bolt of my grinder trying to undo it as though is had a regular right handed thread, now I'm trying to find a replacement low profile hex head M8 25mm set screw, and it's not must fun.

Thanks again for the help.

 

[Musicphan]

Glad you fixed it... and now you see why i called it coffee glue You may want to see if these guys have you hex screw: https://www.fastenal.com

 

[shadow745]

Yeah I had to use several toothpicks as well as a very stiff (nylon) group brush to remove the coffee tar out of the threads. Since the burr carrier in the Rocky is solid brass I soaked it in near boiling water to help soften the tar. Everything else was cleaned by hand and it took awhile. The grinder was barely used, but thanks to it sitting so long that smell permeated the burrs. Trying to remove them was a bear as two screw heads stripped regardless of the bits I used. Had to very carefully drill out the heads just enough to use a screw extractor and all was good. The burr smell was so bad (and I needed new screws) I went ahead and replaced the burrs/screws so I would have a fresh start. Saved the old ones as a backup.

No complaints though as a few new parts and lots of cleaning is worth the hassle/time for the low used price.

 

[sarah98]

I have no idea of it.