Hacking the DF64 exit chute - Page 13

July 4th, 2022, 4:36 pm

ltanzil wrote:does it work or go without declumper all together. what has better result? i dont mind doing more puck prep such as WDT.

Post #5 in this thread has a picture of the grinds I get when the beans are liberally misted (which can encourage clumping) and the grind setting is pretty fine, about 15 ticks above burr-touch. The grind is textured, but fluffy and very uniform. I WDT, but only to achieve a level tamp.

I suspect that 'clump crusher' is a marketing-friendly name for a flow restrictor. The flow restrictor can significantly reduce static effects, but will also pack the grounds into clumps that need to be broken up. Ironically, I got less clumping by eliminating the clump crusher.

I've seen a few posters on this thread have added clump crushers to the free-flowing exit chute, which is fine. I dunno if it really makes a substantive difference, but it shouldn't do any harm - as long as it doesn't trigger a clog. I've observed a dark roast (oily) fine grind stacking up on a thin piano wire - which eventually triggered a massive clog.

#122: Post by **CM00** » July 6th, 2022, 4:51 pm

GDM528 wrote:I printed up a copy of the larger aperture chute, and captured high frame-rate videos to compare the output streams. Each video is 1 second of real-time, captured at around 250 frames per second, then remapped to 30 frames/sec for the posted videos. I say 'around 250' because I couldn't lock the frame rate. So the original chute frame rate is 238 frames/sec and the new chute is 266 frames/sec - useful to know if you try measuring movement per frame.

I grind finely for espresso, about 10 ticks from burr-touch with the original Italmill burrs. The beans were a hybrid Full City roast with an odd grind behavior due to an admittedly bizarre home-roasted profile - that should be largely inconsequential for the purposes of this test, but hey, full disclosure. I imagine a light roast / coarser grind for pour-over would behave a lot differently, so YMMV. I also went extra-heavy with misting the beans to get the grind to clump up a bit more to make it easier to track movement in the video.

First, the original version of the exit chute:
video

Next, the latest larger-aperture chute:
video

They look pretty close to me, however, the width of the stream of grounds is wider with the larger aperture chute. If the grind rate of the burrs is the same, a wider stream would have to run slower, or be more dispersed across the wider stream, which my brain could interpret that as appearing slower, although in this case too subtle for me to pick up on. This might be more apparent at a different grind setting.

Installing the new chute requires removing the base plate, which will likely shift the burr position unless the screws are exactly tightened as before the swap. Even though I used the same beans, there was a significant difference in the flow rate of the shot I pulled - it was faster, which generally implies a coarser grind, which in turn may affect how the grind flowed through the system.

So, my observation is the flow was largely the same. I'll keep the larger aperture chute installed to monitor accumulation inside the chute. And on that point, here's what the previous chute looked like after many weeks of usage without any deep-cleaning maintenance:
image

The total accumulation is much less than 0.1g and was pretty firmly entrenched, such that it would take a probe/pipe cleaner/brush to remove it. I attribute some of the stickiness to the roast level of the beans I run through the grinder, as the oil from the Full City roast level may be acting as a binder, and the fine grind isn't abrasive enough to clean off the deposits. It will be interesting to see how the larger aperture version will behave...

I come back on this, indeed the flow is the same after this testing period. The chute remains clean, little to no deposit at all which means no retention and low fines.
And you were right also about the DF64's final frontier - static issues! I try to RDT as much as possible but when my wife makes her afternoon coffee the mess on the table/grinder is quite visible ( do she hates the grinder and thinks it is useless).

Thanks once again!
CM

#123: Post by **iyayy** » July 6th, 2022, 11:13 pm

um.. is static worse with the chute?
what about inclusive of nozzle and dome thingy?

i used a modified clump crusher and dont rdt. it keeps my shots result consistent, only have small mess on dark roasts, barely any mess with med or lighter roasts.
i tried without clump crusher and its ridiculously everywhere.

am considering this since i like the unrestricted flow to shoot out grounds without possoble regrinding, but not gonna do rdt.

#124: Post by **ShotPull** » July 6th, 2022, 11:26 pm

Has this issue been fixed on the latest release of this grinder?

#125: Post by **Jeff** » July 7th, 2022, 12:56 am

This thread is still very relevant with the June batch through Espresso Outlet. Though there have apparently been some improvements made to the upper burr carrier, the declumper and chute are seemingly unchanged. I have not seen changes to either of those reported in other markets.

July 7th, 2022, 1:04 pm

That's correct. Per Joe Kolb at Espresso Outlet, who's pretty much the only seller that keeps updating the DF64 info on his website

...
the newest batch has an improved upper burr carrier, new font on the dial, updated burr screws, burr seals, metal grind indicator, updated switch as well as an updated declumper (I haven't seen a picture of it yet).

https://www.espressooutlet.net/turin-df ... o-grinder/

Good to know that although it's taken a long time, the company is listening and making changes. An updated review from on of the influencer might be in order soon

Here's a picture of the metal grind indicator and new font from the FB group:

#127: Post by **ShotPull** » July 7th, 2022, 1:56 pm

Oh, okay, good to know. I've only had mine about a week. It looks exactly like the one in the picture above. I haven't sold my Specialita yet but I will now.

Except for a little fine dust here and there (expected) it seems to be working great. Now if I can only get it dialed in perfectly ...

July 7th, 2022, 2:36 pm

3D cup raisers and angled forks are great solutions to keep all the grounds inside the dosing cup.

July 7th, 2022, 3:58 pm

iyayy wrote:um.. is static worse with the chute?
what about inclusive of nozzle and dome thingy?

i used a modified clump crusher and dont rdt. it keeps my shots result consistent, only have small mess on dark roasts, barely any mess with med or lighter roasts.
i tried without clump crusher and its ridiculously everywhere.

am considering this since i like the unrestricted flow to shoot out grounds without possoble regrinding, but not gonna do rdt.

In principle, static should be worse with the unrestricted chute design. The grounds spend considerably less time in the grinder, where they can drain off some of the charge transferred by the burrs (triboelectric effect). Not everyone seems to be reporting increased static issues however, nor have I noticed a difference. Yet others have observed an intolerable amount of static spray, which I think indicates how many variables are involved in the effect.

I have a zero-tolerance policy for my grinder making a mess, so I use the downspout and expansion chamber to contain all the grounds long enough for them to discharge in the catch-cup or portafilter. Others have reported acceptable static without the downspout/expansion chamber, but they may be misting the beans, lighter roast, coarser grind, more humid climate, etc.

July 7th, 2022, 4:07 pm

Jeff wrote:This thread is still very relevant with the June batch through Espresso Outlet. Though there have apparently been some improvements made to the upper burr carrier, the declumper and chute are seemingly unchanged. I have not seen changes to either of those reported in other markets.

The manufacturer may be stuck with their chute design due to the constraints on injection-molded parts. Switching to a 3D-printed exit chute would add about two dollars to the manufacturing cost - that may not sound like much compared to the overall selling price, but when you're focused on profit margins...