CanadianExpress wrote:The base is square and measures 92mm or 3 5/8" wide

The base is also 34mm or 1 5/16" tall

Thank you!

I have had the WDT DUOMO for some time now. I have the first generation. My experience has been the complete opposite. My problem is that the extractions seem to blond and taste underextracted everytime I use the DUOMO. I have to use a leveling tool after using the DUOMO or otherwise I get a massive donut extraction. The extractions are even when I use the DUOMO + a leveling tool, but the flavor is always weak and underextracted. When looking at the bottom of a bottomless portafilter the color is almost cream/yellow compared to the regular brown when all I use is regular WDT with a needle. Yes, this is using the same coffee. Going finer obviously causes the shot to extract slower, but it still blonds way too fast when using the DUOMO. The dry puck also always has pin holes when using the DUOMO. I know I am getting some type of channeling since that is the only explanation, but since the extraction looks even and centered it is not obvious. I have never been able to figure out why it doesn't work.

I'm interested in how people are using this tool with success as I've had no such luck extracting anything decent?

My process
- Grind into Lagom cup then dump into portafilter
- Set Duomo and spin slowly 2 full revolutions
- Remove Duomo and give one light tap on table to settle grounds
- Tamp with Eazytamp
- Pull shot riddled with deadspots and channeling

I've tried different needle depths (currently have it set at 23.5mm with my 18g vst basket being around 24mm deep), doing more/less revolutions and incorporating the Pullman chisel back into the routine after the Duomo step.

Honestly, my routine isn't much different. I might turn it a time or two more, but never really found it to make a different. Do you have the original one or the newer "Eight" version? Maybe the new pin layout makes a difference? Tough to think that would should make such a difference.

Perhaps you have the pins too deep and they're compacting coffee under the pin paths, plugging off circle patterns of basket holes? Just a thought; based purely on speculation. I'm no cafeologist.

On the other hand, I'm relatively new to high quality home espresso. I just dumped thousands of dollars on equipment and began figuring it out through trial and error, and plenty of online tutorials. Maybe I'm pulling terrible shots and just don't know what a good one is. That being said, I've had lattes from the coffee roaster where I buy the beans, and I find I enjoy the ones I make at home just the same.

I hope more people comment on their DUOMO experiences because like I mentioned above I have owned the Duomo for a long time and I believe I have tried everything and still cannot get one drinkable shot with it. I have tried using it:

1. Alone with a minimum of 4 and up to 10 revolutions and tamp. This always results in massive donut extraction unless I use a leveling tool.
2. same as above but give the portafilter one or two vertical knocks then tamp.
2. with a leveling tool(Jack Leveler or Pullman Chisel) and tamp.
3. different needle depths from all the way down touching the bottom of the basket up to several millimeters above.
4. I have even tried WDT with a needle and then using the DUOMO.

All of these results in a very thin, watery underextracted coffee that tastes very unbalanced. The extractions look beautiful and centered as long as I add the leveling tool then tamp to the process, but it goes blond and watery extremely fast. Using WDT(dissecting needle) alone transforms the flavor of the shot for the best. The liquid comes out syrupy and takes forever to blond. The smell, body and taste is completely different to what the DUOMO gives me. Again, this is using the same coffees and YES, I have tried grinding finer when using the DUOMO, but it doesn't help. I can make the shot extract really slow, but it still blonds way too fast and tastes horrible.

You may ask why did I buy the DUOMO if I was getting excellent results with regular WDT? Well, WDT is not something that works 100% of the time unless it is done correctly every single time. Sometimes even using WDT I get subpar extractions because for example the way I moved the needle caused a larger amount of grounds to move to one side of the basket. Yes, technique is important when using WDT. I can usually get 6 good shots out of 10 with WDT. The DUMO looked like something that would make up for my own technique inconsistencies, but so far it has not lived up to expectations. The thing is in theory it should work, but for some strange reason it doesnt.

Uploaded a quick video to show a simple puck prep straight from the grinder. Sorry for the one handed video. Grind was a bit too course and it got a little fussy on the bottom of the VST basket but it still tasted good.

http://www.youtube.com/watch?v=2xDjey2VRtw

Thanks Dimitri for taking the time to post the video, must be user error setting the needle depth on my end I think will have to keep playing.

FWIW I adjusted my technique several times before recently settling on this approximate method. Also I don't normally tap on the counter more than once or twice, don't ask me why I tapped so many times in the video! I also recently raised the height of the needles a little from where I started in the lowest possible position in the 20g VST and I think it has helped with consistency.

Now that I've had the Duomo for a while longer, it's time to provide an update. I have noticed that after turning it several times, the coffee tends to be a bit more concentrated around the outer portion of the basket. I'm going to chalk this up to centripetal force. I bet you didn't think you'd have to recall anything from high school science class today! This was more noticeable in a 22g basket with a 20g dose than it was previously with an 18g basket using an 18g dose. The base of the pins in the Duomo likely prevented this from happening before.

I've since reincorporated the OCD back into my routine, after the Duomo and before tamping. This has resulted in a more picture perfect extraction. I thought the shots I was pulling before were pretty good, but I am relatively new to chasing the espresso dream at home. They used to taste pretty good, but still dance around the bottom of the portafilter more. Now the steady stream meets in the middle almost immediately and stays there throughout.

Upon watching the video dak posted, I saw he was using filter paper. So of course I had a new rabbit hole to go down. I ordered the Cafelat Robot filters. Here's hoping they're the right size. I don't have it in me to add "trimming filter paper" to the mix.

I wonder what other small variance I'll discover next that I can obsess over...

CanadianExpress wrote:

Upon watching the video dak posted, I saw he was using filter paper. So of course I had a new rabbit hole to go down. I ordered the Cafelat Robot filters. Here's hoping they're the right size. I don't have it in me to add "trimming filter paper" to the mix.

I wonder what other small variance I'll discover next that I can obsess over...

I use the Robot filter papers; they fit perfectly with VST baskets. I use them on every shot for 2 reasons. First, they help keep your grouphead MUCH cleaner than without. I remove and clean my IMS dispersion screen about once a month, and since I started using the filter on top, I don't know why I bother as it is usually spotless with a hardly noticeable oil film (nano tech coating actually seems to help with this too). The second benefit is better water dispersion on top of the puck to help reduce / eliminate channeling. I pull it off the top of the puck before knocking it out, rinse it off and let dry on the drip tray for the next shot. I can usually get 5-10 shots before tossing it.

Also, FYI, if you ever want to try the double filtration method, (filter on the bottom for light roasts lungos / blooming profiled shots) I use the ones linked below for the bottom of the basket. Perfect fit for the bottom diameter of the VSTs and good flow, but these are not easily reusable so I just chuck them with the puck.

https://www.amazon.com/gp/product/B00NG2E9MO/