I am mystified about the method of setting the fineness of grind on my RR45 grinder. The upper burr holder has 50 click stop settings on the outer ring. I have found that my espresso machine, Faema C85, is very sensitive to the setting. It seems that +/- 1 click stop from the one which gives the best brew time, approximately 25 seconds, will either blind the filter or give a 10 second brew time.

I measured the thread pitch of the burr holder at approximately .030" per thread. With 50 click stops per revolution, this means the burr moves up or down by 0.0006" per stop. How can such a small movement have such a large effect on the fineness of grind?

I did replace the burrs which now have about 20 pounds of coffee through them.

David6FL wrote:How can such a small movement have such a large effect on the fineness of grind?

Are you using fresh coffee (roasted within the last 10 days)? Stale coffee will exaggerate the effects of grind setting changes, i.e., the grind setting tolerance for stale coffee is razor thin.

The stepped settings on the RR45 are a pain; I prefer the stepless Mazzer I replace my Rossi with.

Anyway, how are you dosing? Have you considered getting the grind in the ballpark and fine tuning the dose?

I believe you can get a finer adjusting step ring, btw, but it may not be a huge improvement.

HB wrote:Are you using fresh coffee (roasted within the last 10 days)? Stale coffee will exaggerate the effects of grind setting changes, i.e., the grind setting tolerance for stale coffee is razor thin.

I have not observed that the "freshness" of the coffee makes any difference. I buy my coffee at a local Italian market where they roast their own. Their espresso bar has heavy traffic so I feel any beans I buy there are fresh. I am ready to make new buy of beans. I use about 2.5 pounds per month.

I use the doser on the RR45. However I am ready to change. The doser will not consistently drop more than about 13.5 grams. That's with the doser chamber all the way up.

I just can't believe that 0.0006", that's 6 ten thousands of an inch, makes any difference.

I assure you that coffee freshness makes a huge difference in the grinder setting's margin of error. Even with a stepless grinder, the "espresso zone" is far narrower if the coffee isn't fresh. The similar comment applies to decaffeinated coffee, i.e., the grind setting is more critical and the coffee stales more quickly. You can try modifying your grinder to allow for finer-grain tuning, but my recommendation is to start by picking one of the popular espresso blends from the List of our favorite Roasters. At a minimum, that approach will allow forum members to offer specific diagnostic suggestions based on their experience with coffee X versus what you report.

I've got a Rossi RR45 doserless with the 80 pin collar that's working fine and does an excellent job grinding for espresso. Mine just fits under the cabinets so I dump 15-20 grams of beans in the throat and put a tamper on top. You might want to investigate changing out the adjustment ring if you plan on keeping the grinder.
Rossi RR45: 48 to 80 position conversion question

I did a clumsy stepless conversion on mine: I removed the parts that hold the setting in place, then I drilled a hole through the ring slightly smaller than a bolt, screwed the bolt in from below, then attached a nut, wingnut, and another nut on top and tightened them together. Then you use the wingnut to tighten or loosen the bolt against the grinder body.

I can take a picture later if it helps. This worked for me for 6 years, then I got a good deal on a Compak grinder. A better method would be to use a threaded insert.

I don't remember the steps begin as far apart as you experienced, but that they were indeed pretty big. My memory is that 2-3 steps would make something that could be called espresso; I hastily came up with the stepless bodge.

hankua wrote: I dump 15-20 grams of beans in the throat and put a tamper on top.
Rossi RR45: 48 to 80 position conversion question

I just picked up a Rossi RR45 with the intent of charging in exactly this manner--sans hopper. But mine won't run with the hopper removed (please see my post about this elsewhere on this forum: "Rossi RR45 won't work without hopper in place"). Apparently, there is some sort of switch that prevents it from operating without the hopper. Sigh. Do all RR45s have this "feature" (or am I just lucky )? Obviously, hankua doesn't have this problem. If there is a mod to bypass this switch, could someone please provide a step-by-step guide? I'm flummoxed!

cheers,
Aden

Aden wrote:Sigh. Do all RR45s have this "feature" (or am I just lucky )?

My vintage RR45 does not have this feature.
I bought it (well) used from a pawn shop back in 1993ish.

Thanks, Allon (you lucky dawg!). Can ANYONE provide a tutorial on how to bypass this a%$#@ switch?