# Static problems - anybody providing a ground connector?



## fenix (Oct 31, 2010)

I get static issues with my RR45 grinder, and reading one of the Niche threads (hope to get one next year) some people are getting a small amount of static. Just wondered if anybody has tried an earthed antistatic mat, and connected the grinder to a dedicated chassis earth? Keeping the grinding cup on the mat might also help. Sounds strange but what you have on your feet can affect how well you provide a suitable escape for static. Some worktops could be conductive while others aren't, etc.


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## El carajillo (Mar 16, 2013)

Static is a complex problem, no simple answers. I have tried various earthing solutions without any success. Many other members have tried differing solutions , some improve matters others make no difference.

Certain beans are known to be problematical M Malabar ??

At the moment I am using my Hausgrind and the grounds are clinging to the sides in a perfect tube formation WHY ???









By gently wiping a plastic strip around the inside of the container the coffee grounds collapse into a soft heap, has the static discharged through me ? Did I generate the static ?


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## L&R (Mar 8, 2018)

For me a drop of water in beans before grinding helps, no matter of grinder.


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## Jollybean (May 19, 2013)

Yes I use a couple of drops of water on my HG1 which works well but I think Dave does not recommend this for the Niche as it may make the high tech slippy internals sticky, increasing retention.


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## ajohn (Sep 23, 2017)

It's complex all right. I weigh in a lot of my shots using a Mazzer mini and lens hood arrangement. I've added a small weight that sits on top of the beans. I've found it alters the grind a bit but also keeps all of the bits of grind down in the area of the burrs rather than some finishing up on the lens hood etc. I have to brush the area down but what goes in comes out. The weight is just a bit of left over aluminium I had lying about that was mushroom shaped. It can tilt as it goes down so recently I started lightly supporting the narrow part when the grinder was running. Pressing on it wasn't a good idea - too much variation.








Anyway the 2nd time I supported it my fingers touched the rest of the metal work and I received a bit of a shock - static so now I make sure my fingers are also touching it right from the start. Given where small quantities of grinds finish up static is still having an effect where the grinds come out of the funnel. There is also always slight traces of grinds inside the funnel - that could be down to oily beans though but they brush off easily. Clumps - since the burrs have really run in I don't get them other than odd splats that come out of the grind chamber and they are very very loosely packed.

John

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## Hasi (Dec 27, 2017)

Telling from my experience, it's got to do with a bean's humidity.

Adding a drop of water kinda proves my point:

Straight after the roast, beans are almost totally dry. Any remaining capillaries, bean temp, dew point, ambient temp and humidity - there you have your recipe for moisture will re-enter the beans.

The less time coffee is then being exposed to air, the drier it'll stay. If it hasn't been quenched, of course.

You could therefore derive some sort of quality sign from a static coffee: freshly roasted AND immediately packaged but NOT quenched = static.

___

Still, we're facing static issues on our Mahlkönig Guatemala shop grinder, it has a plastic cover over its foot and attracts grinds as hell!

Tried with a tin cup connected to earth, tried with different shoes, without shoes (







) - no luck. Especially critical when grinding a whole bag of coffee and sh!t goes everywhere but back into the bag









Gotta try the water drop next time!


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## El carajillo (Mar 16, 2013)

The tumbling effect while roasting and the rubbing together would help create static .


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## DavecUK (Aug 6, 2013)

years ago I experimented with earthing grinders, makes no difference. If you think about it your grinder is already earthed if it's a metal bodied one or a grinder where the electronics/motor are earthed.


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## Hasi (Dec 27, 2017)

I'd say it's more the rubbing together during grinding.

Aren't many metal parts in a modern grinder made of cast or machined aluminium? At least in my Macap MXP that's the case (







)

Aluminium doesn't have a very high conductivity: so case, burr carriers, adjustment threads, hopper inlets might not help conveying weak currents. Just a thought, though.


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## DavecUK (Aug 6, 2013)

Hasi said:


> I'd say it's more the rubbing together during grinding.
> 
> Aren't many metal parts in a modern grinder made of cast or machined aluminium? At least in my Macap MXP that's the case (
> 
> ...


Aluminium is a pretty good conductor, I wouldn't worry about that. Also static electricity is a surface carried charge, not quite the same in terms of conductivity. Remember steel has a lower conductivity than Al and they always earth a steel case.


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