Rancilio Rocky - Burrs wont touch.

Grinders are one of the keys to exceptional espresso. Discuss them here.
sgx
Posts: 13
Joined: 13 years ago

#1: Post by sgx »

Hi all,

I wonder if anyone can shed any light on a problem I'm having with the Rancilio Rocky?

I took the thing apart today to give it a good clean before I started using it for espresso again. Once cleaned I tried screwing the top burr back on again, but found that I cannot screw it down enough for it to touch the bottom burr. *Or maybe I can and there is another issue...?

I had a look on a couple of YouTube clips from Seattle CG etc. They state that once you get the 2 burrs to touch you know your at the zero point and can then work from there. They demonstrated the two burrs touching, which meant that screwing down the top burr any further caused both burrs to move in sync.

However, after screwing down the top burr as far as it will go, it will not cause the bottom burr to move at all...

Any ideas why my top burr wont go down far enough?? I'm stumped...!

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another_jim
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#2: Post by another_jim »

Clean the threads with a slightly oily cloth, perhaps; small coffee particles can stop them from turning.
Jim Schulman

genovese
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#3: Post by genovese »

sgx wrote:Hi all,

I wonder if anyone can shed any light on a problem I'm having with the Rancilio Rocky?

I took the thing apart today to give it a good clean before I started using it for espresso again. Once cleaned I tried screwing the top burr back on again, but found that I cannot screw it down enough for it to touch the bottom burr.....Any ideas why my top burr wont go down far enough?? I'm stumped...!
Interference from the stop screw that sticks out from the bottom of the hopper? You may have reattached the hopper to the upper burr carrier in a different orientation (there are 3 choices) than it began with. The screw is there for good reason, but if it's in the wrong location, it will interrupt adjustment in the useful range of the threads, which is within the first 180 degrees or so of burr-zero. It's the unlabelled screw at the center of this diagram:



So take the hopper back off, rotate 120 degrees and try again.

sgx (original poster)
Posts: 13
Joined: 13 years ago

#4: Post by sgx (original poster) »

another_jim wrote:Clean the threads with a slightly oily cloth, perhaps; small coffee particles can stop them from turning.
Good call...
I've checked and their all super clean though.

sgx (original poster)
Posts: 13
Joined: 13 years ago

#5: Post by sgx (original poster) »

genovese wrote:Interference from the stop screw that sticks out from the bottom of the hopper? You may have reattached the hopper to the upper burr carrier in a different orientation (there are 3 choices) than it began with. The screw is there for good reason, but if it's in the wrong location, it will interrupt adjustment in the useful range of the threads, which is within the first 180 degrees or so of burr-zero. It's the unlabelled screw at the center of this diagram:

<image>

So take the hopper back off, rotate 120 degrees and try again.
Hi genovese...

I actually removed the screw your talking about white a while back to enable me to get a finer grind. The company I bought it off said this was OK, so long as I didnt adjust the grind setting whilst it's running.

So no, it cant be that...

I've just looked again and there appears to be quite a gap between the 2 burrs. Is there anything that could be affecting the bottom burr to be too high??

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another_jim
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#6: Post by another_jim »

Misaligned threads? Have you unscrewed it and tried again?

What you are describing seems impossible, the threads should continue to screw indefinitely until something stops it; i.e. the burrs touch. If something is stopping it ahead of that, it should be visible or touchable.
Jim Schulman

genovese
Posts: 210
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#7: Post by genovese »

sgx wrote:Hi genovese...
I actually removed the screw your talking about white a while back to enable me to get a finer grind. The company I bought it off said this was OK, so long as I didnt adjust the grind setting whilst it's running.
They're half right. The screw is was there to prevent the hopper unscrewing if you depress the adjuster lock button while it's running WITHOUT holding the hopper to prevent that. If there is coffee between the burrs, adjusting a non-running grinder to a finer setting may mash coffee into the burrs, which can prevent the motor from starting, and may require disassembly to clean. Since you can't see whether the burrs are clear of coffee, it's better to adjust while running the grinder, with one hand holding the hopper and the other on the release.
sgx wrote: I've just looked again and there appears to be quite a gap between the 2 burrs. Is there anything that could be affecting the bottom burr to be too high??
Sorry; I don't follow you. If there is "quite a gap," then either the lower burr is too low, or the upper is too high, unless one of us is looking at it upside down. Ignoring that for now, it sounds like the threaded collar is not screwing all the way down into the bore.

IF it is stopping gradually due to friction/tightness, then follow Jim's advice and clean the threads, and while you have them exposed, inspect them for cross-threading or other damage.

OTHERWISE, if you are feeling a "hard" stop as you screw the carrier down, you have an obstruction, like a stray object, maybe a bean or a bit of metal, between the burrs. Or you may have a loose screw with a projecting head that's in the way. Or, if you removed burr(s), one may be cocked at an angle if it's not seated all the way. Even a tiny bit of debris behind the burr could cause that.