^ I'm using my Arco in electric mode and even with 2 spritzes of RDT I need to remove the grinder portion, each time, to gently tap it on the counter to dislodge most of the grounds that static cling to the bottom burr area. I think, but won't know until I give it a try, a bellows might be the answer and keep wear/tear of removing/reinstalling the grinder to the motor housing to a minimum.

I have sent an inquiry to a couple on Etsy that make a silicone bellows & adapter for the Mignon grinder, about making an adapter & bellows for the Arco.

boren wrote:Can a blower be used to reduce retention (instead of slapping or tapping the grinder)?

I would rather try to build a chaff trap accessory inspired from Airmill project:
https://www.kickstarter.com/projects/co ... ee-grinder

Something like a mini cyclone mounted between the grinder exit and the grounds collector, using same magnetic principle.

renatoa wrote:Goat, look below what vox populis commend
See that taper between the body wall and the outer burrs ?

image

Yes, what are you trying to tell me with this picture of the taper?

Is a solution for beans not falling inside the burrs, but remaining on the edge.
RDT is not a cure for this issue.

I just tap on the top and the rare been that has been stop will drop into the grinder. Too much water for RDT will case it to stick more.

Mukka wrote:I've used the recommended range printed on the bottom of the catcher and it was fine.

really? I don't use it that often but my Arco grinder by hand, is way too coarse using their guidelines at the bottom, even when I'm at the lower end, I need to go half a big number rotation down or a full rotation down to get what they're suggesting

You should report your copy at manufacturer, or seller, for recalibration.
In our local community, with more than 20 units acquired, all are within limits, mostly at lower limit, but still in the range.
Mine is set at 32 for espresso, as an example, or 1.30-1.50 for most pour over devices I am using.

To anyone struggling with static and coffee build up at the bottom of the grinder, here's what I've been doing lately.

RDT
Turn grinder ON
Dump beans inside
When grinding is done I use a camera lense blower and blow upwards with the catching cup partially tilted but still on so it catches whatever grinds that fall.
I have a blower with a soft spout which works great for this.

I've tried this with med-dark roasts lately and have had no issues whatsoever. I don't knock the grinder on the counter anymore as I was never fully confident doing so...

It's also obvious that static and retention/build ups have improved greatly with burr seasoning.

For brew only, the static is a feature, not something to fight against. Imo...
I let the static to do it job, accumulate everything, and blow that fraction separately, not in the grounds colector.
Please do this and examine with a magnifier what is retained by static: chaff and fines. Nothing I want in my cup.

For espresso, things could be different, fines are desirable, in a certain amount, and chaff became too fine to be separated from the grounds. So it's ok for espresso try any method against static, RDT or whatever blower.

I have my doubts...if retention was a design feature.