DF64 - retention issues even with declumper completely removed?

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cactus_farmer

#1: Post by cactus_farmer »

I removed the declumper completely from the DF64. This removes the physical obstruction preventing grinds from migrating through the chute, but causes so much static to be built up that seemingly every inch of the inside of the grinder is coated with powdered coffee - which is another form of retention.

Have people found that this internal static cling retention is actually worse than the retained coffee being stuck behind the stiff declumper?

NOTE: when removing the declumper I found that simply screwing the chute back on causes the screws to jut out just far enough to stop the burr from spinning. The 1.5mm thick silicone declumper also serves to ensure the screws do not jut out and block the burr from rotating - therefore you need to replace the declumper with anything else that is also 1.5mm thick

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Brewzologist
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#2: Post by Brewzologist »

Hi Marc; there is quite some information avaialable you can search within the threads below on for the declumper, retention and static and what others have done to address the issues you mention:

G-IOTA / DF64 espresso grinder
Hacking the DF64 exit chute

In short, I run without the declumper, using the hacked chute and RDT. With this I have minimal retention and static. (Static to some degree is something you have to live with in the DF64, but it can be reduced.)

imp96

#3: Post by imp96 »

I had exactly the same experience as you. The static isn't a huge issue for brew but for espresso the buildup in the chute due to static is huge. Not only that, but the bellows are hit and miss when it comes to getting everything out of the chute. This also the reason why I think all the claims that there are more fines produced due to the declumper are wrong. The real issue, I think, is that the finest particles are the ones that get stuck in the chute, and they are what get bellowed out at the end.

iyayy

#4: Post by iyayy »

i diy thin soft flap. was interesred in the chute but since im happy with how it is im leaving it.

without declumper i didnt like it. very messy with dark roasts. didnt really test retention, but there was enough dust everywhere on and inside that i quickly diy and installed some flap.
i assume that managing chamber pressure is more important to static, and the flap keeps that while allowing ground coffee weight to just push out.
im mostly at 0.1g or less (scale didnt pick up) after bellows on espresso (even at my common 2pt before chirp).

there is definitely some continues small build up in the chamber.
i blow these out by running the grinder and bellows when i do filter (usually 70~90) or change beans. i'll maybe get about 0.5g if i havnt done this for more than a month.

i never had issues with any noticeable contaminated flavor even changing dark to light or brew method, or remotely approaching buildup. last i popped for cleanup i only dust off those that sticks within burr gap and cavity, didnt weight it but looks about 2g+.

note that i avoid rdt at all cost.
i feel this is main culprit.
subsequent grind will develop clogging and reduce bellows efficiency. even puring beans on from damp cup can clog it.
it also messes shot consistency. this is noticeable when i have guests or testing beans and pulling more than 3 cups. without rdt, as long as i bellow i will be within 0.1g or less, i can even use my timed auto on my bdb to get consistent taste and balance, yield may vary slightly due to very minor puck prep and small gram difference.

i switch beans, brews and shot regularly, but keeping myself to mostly around 40g per say, or 3~4 cups depends on method.

ltanzil

#5: Post by ltanzil »

i have tried to remove the the declumper and it occasionally clog especially on dark roast and low rpm. i found the culprit is the exit chute design. since i changed the exit chute to a simple 19mm brass tube. the clogging issue is gone. even without declumper

cactus_farmer (original poster)

#6: Post by cactus_farmer (original poster) »

One more question about the grinder - are you meant to leave it on all the time - or turn if off at the plug? (Which would be a bit annoying because I'd have to pull out my microwave every time I want to turn the grinder off at the wall...). The power button stays lit all the time. Is the motor definitely completely off when that's happening?

cmin

#7: Post by cmin »

ltanzil wrote:i have tried to remove the the declumper and it occasionally clog especially on dark roast and low rpm. i found the culprit is the exit chute design. since i changed the exit chute to a simple 19mm brass tube. the clogging issue is gone. even without declumper
What and how did you do the 19mm brass tube? I'm interested, I have a DF64. I keep around for whatever reason lol. Worst "single dose" grinder ever even with alignment and modding lol. Heck even a ceramic burr Vario is better in the cup and flawlessly single doses w/ 0 issue (no wonky ass bellow blowing dust everywhere) and even better aligned.

But glutton for punishment, I still keep this DF64 to compare with other grinders. The chute design is so ass backwards, I'm pulling Sweetblooms Home blend right now and even that gets caked up and than blows chunks or dust everywhere.

rsn4534

#8: Post by rsn4534 »

There are reasonably cheap demagnetizers you can google and many will pop up. I'm wondering why some of these gizmo's would or wouldn't work on the DF64.

ltanzil

#9: Post by ltanzil »

cmin wrote:What and how did you do the 19mm brass tube? I'm interested, I have a DF64. I keep around for whatever reason lol. Worst "single dose" grinder ever even with alignment and modding lol. Heck even a ceramic burr Vario is better in the cup and flawlessly single doses w/ 0 issue (no wonky ass bellow blowing dust everywhere) and even better aligned.

But glutton for punishment, I still keep this DF64 to compare with other grinders. The chute design is so ass backwards, I'm pulling Sweetblooms Home blend right now and even that gets caked up and than blows chunks or dust everywhere.
It is simple basicali i just soldering 2mm brass plate to 19 mm OD brass pipe. for the picture you can look at this thread

Hacking the DF64 exit chute