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Author Topic: Grind adjustments whilst grinder is turned off  (Read 1641 times)

Simon

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Grind adjustments whilst grinder is turned off
« on: 22/08/2017, 12:50 PM »
Thought I'd pose the question, it's been discussed many times elsewhere, but the question is:

Is it safe for you to adjust the grind finer/coarser without it running?

I've seen completely opposite views, just looking for a definitive answer (if there is one!), and I guess it may depend on the grinder itself regarding how big of an adjustment occurs.

I've seen it said absolutely do not do this under any circumstance, will cause the burrs to misalign, DESTROY the motor, stall the grinder etc because of beans being jammed and you're trying to squash it all together.

And the opposite saying: totally fine to do if it's a small adjustment (some even say fine for large changes too), the burrs are much much harder than beans (which you can easily break with your fingernails), so it won't cause any damage whatsoever to the burrs.

Some also say it's totally okay to adjust coarser while the motor is off, but you should run it when adjusting finer.

What do you guys do, or what is the general understanding? :)


*EDIT: I just adjusted my grinder one notch finer, whilst the hopper, throat, and everything was full of beans and whilst being turned off. And the grinder did not, I repeat, did NOT explode XD. Nor was there any resistance I felt as I changed it, which there would probably be if partially ground beans were jammed in between the burrs


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samuellaw178

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Grind adjustments whilst grinder is turned off
« Reply #1 on: 22/08/2017, 04:28 PM »
I guess it depends?  :P If you're using a tank-like commercial grinder, it doesn't matter what you throw at it. But if the grinder has plastic mechanism (the low end ones especially), the plastic part will probably crack even without you touching it!  :rofl:

mycuppa

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Grind adjustments whilst grinder is turned off
« Reply #2 on: 22/08/2017, 04:58 PM »
Simon, it does matter and this applies to all grinders, even more so the larger grinders. Heck, for large grinders there are actually warning in the owner's manual about NOT making adjustments without the motor running.

Sadly, most of the stuff written on forums is constrained to limited experiences or even more limited understanding of the actual impact, so I would disregard most of what you may have read in the past and form your own opinion.

Speaking from someone who has to grind 50+ kilos of coffee every single day - all different settings, across a number of different grinders, here is my gospel.

Using an assumption most grinders have a bunch of "stuff" around the burrs (call it what you may, but there is some partially ground coffee jammed in there it seems all of the time) let's further assume you are trying to dial in a grinder (the original reason you wanted to make an adjustment) and for this to occur properly you need some beans in the hopper to avoid the dreaded "bounce" effect.

I'm not going to discuss in detail a scenario of an empty hopper - that's got a whole bunch of other challenges, but an empty hopper and cleaned out grinder should allow a freer adjustment.

If you are attempting to make a minor coarse adjustment, I've found it's ok to make this without the motor running as you are in essence releasing a tiny amount of tension.

For a finer grind adjustment, it's logical that you are going to "crush" partially ground coffee into "hammertime chunky clusters".

Now it gets interesting.......this produces particles that will choke and channel in the next shot (or shots) unless carefully distributed, hence causing your brain to get fried in the whole "what's going on with this damn thing today........".....aka......distressing.

On my Robur-E, if I make a grind adjustment without the motor running, the stupid grinder gives me a bunch of illogical results for the next 3 shots (sometimes more if the hopper is low) until it settles itself down again. If I was naive and inexperienced, I might have kept making knee-jerk adjustments and find myself chasing my tail around and around (yes, I think I've done that enough times over the last few decades to brand myself naive).

Make some similar adjustments with the Robur motor running and those next few "wobbly" shots are more manageable - or perhaps I'm more tolerant as I grow older.

Bottom line Simon - how much coffee can you waste in the search for the holy grail ?


 


Simon

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Grind adjustments whilst grinder is turned off
« Reply #3 on: 22/08/2017, 10:42 PM »


I guess it depends?  If you're using a tank-like commercial grinder, it doesn't matter what you throw at it. But if the grinder has plastic mechanism (the low end ones especially), the plastic part will probably crack even without you touching it!  :rofl:

Hehe true, cheers :)

Simon, it does matter and this applies to all grinders, even more so the larger grinders. Heck, for large grinders there are actually warning in the owner's manual about NOT making adjustments without the motor running.

Sadly, most of the stuff written on forums is constrained to limited experiences or even more limited understanding of the actual impact, so I would disregard most of what you may have read in the past and form your own opinion.

Speaking from someone who has to grind 50+ kilos of coffee every single day - all different settings, across a number of different grinders, here is my gospel.

Using an assumption most grinders have a bunch of "stuff" around the burrs (call it what you may, but there is some partially ground coffee jammed in there it seems all of the time) let's further assume you are trying to dial in a grinder (the original reason you wanted to make an adjustment) and for this to occur properly you need some beans in the hopper to avoid the dreaded "bounce" effect.

I'm not going to discuss in detail a scenario of an empty hopper - that's got a whole bunch of other challenges, but an empty hopper and cleaned out grinder should allow a freer adjustment.

If you are attempting to make a minor coarse adjustment, I've found it's ok to make this without the motor running as you are in essence releasing a tiny amount of tension.

For a finer grind adjustment, it's logical that you are going to "crush" partially ground coffee into "hammertime chunky clusters".

Now it gets interesting.......this produces particles that will choke and channel in the next shot (or shots) unless carefully distributed, hence causing your brain to get fried in the whole "what's going on with this damn thing today........".....aka......distressing.

On my Robur-E, if I make a grind adjustment without the motor running, the stupid grinder gives me a bunch of illogical results for the next 3 shots (sometimes more if the hopper is low) until it settles itself down again. If I was naive and inexperienced, I might have kept making knee-jerk adjustments and find myself chasing my tail around and around (yes, I think I've done that enough times over the last few decades to brand myself naive).

Make some similar adjustments with the Robur motor running and those next few "wobbly" shots are more manageable - or perhaps I'm more tolerant as I grow older.

Bottom line Simon - how much coffee can you waste in the search for the holy grail ?

Ah, another 21g dose of straight up! Can't tell you how much I appreciate your knowledge and experience on this, thanks Jeff!

Ah that's really interesting, see I would think that the partially crushed down beans (from changing finer without running the grinder) would just be ground out properly in the next shot anyway, and not lodged away somewhere affecting the next few shots, fascinating... but I guess it would possibly push those distorted crushed beans through and into the chute huh, thus being a very different size to the other particles!

I'll take that on board and always grind whilst changing finer. If I'm quick enough with the change it won't waste much coffee anyways.

Appreciate it
Profitec Pro 500, Rancilio Rocky Doser Grinder, 58.5mm Pullman Tamper, V60, Aeropress, Plunger, Behmor 1600

NickC

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Grind adjustments whilst grinder is turned off
« Reply #4 on: 12/10/2017, 05:58 PM »
I've found that I can go coarser without the motor running with no issues, but going finer causes issues - I need to have the motor running to do that. Which makes sense - opening up the burrs should have no negative effect, but closing them will cause a jam.

K_Bean_Coffee

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Grind adjustments whilst grinder is turned off
« Reply #5 on: 17/10/2017, 04:14 PM »
Nice post mycuppa. Spot on.
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Koffee Kosmo

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Grind adjustments whilst grinder is turned off
« Reply #6 on: 17/10/2017, 09:22 PM »
I agree with mycuppa
Course grind adjustment OK 👌 when grinder is stopped
Fine adjustment when grinder is running - although I still do tiny 2 mm adjustments when stoppped

A little quirk of mine is, because of single dosing I start the motor first - and then pour in the beans or open the gate so it’s a smooth - no motor stress- transition to grinding

That’s my way

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askthe coffeeguy

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Grind adjustments whilst grinder is turned off
« Reply #7 on: 17/10/2017, 11:26 PM »
probably my technique is all wrong - but I tend to make small, minute adjustments on the commercial grinders when Im working, when they are switched on, not, Im afraid, out of respect for ware and tare of the grinder, but usually just because Im busy and the grinder is running - if anything Ill close the chute and dump the resulting

However with my domestic appliance at home I almost always make the (minute) adjustment when the machine is switched off - as this is just the way it seems to go - and I havent noticed any deterioration to either shot quality, or ware and tear on the machine

but I can certainly see the argument as to why you should adjust the grinder while its working - Ill keep this in mind for future reference!

Best,

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