Here is the Ultra WDT next to my old faithful "wine cork with sewing needles". As you can see, the Ultra WDT's needles are much thinner and longer. The website quotes .4mm each, and there are eight of them held on by a retainer screw in the body of the tool. The thinness of the needles makes it much easier to break up clumps while stirring, and the length of the needles makes it effortless. With my previous tool, I would frequently hit the wine cork against the coffee bed, causing more clumps than I was breaking. I didn't realize it at the time, but my needles-in-a-wine cork tool was only marginally helpful in breaking up clumps!
The Ultra logo is laser-etched on the top of the tool, which is available in either black or silver. I picked black, both because I enjoy the contrast of the logo against the body of the tool, and because it will match my Ultra grinder when it is delivered. The logo is a stylized view of the top of the Ultra grinder, which is a neat touch and reflects the overall attention to detail. For $32, the build quality is outstanding, and the tool feels very nice in my hands. I have medium-sized hands, and while they used to cramp while stirring with the wine cork, they do not cramp while using the Ultra WDT.
These are the coffee grounds as they come out of my grinder, a hyperaligned Forté with steel burrs. There is some clumping, mostly because I grind into the grounds bin to take advantage of the Forté's automatic grind-by-weight. The coffee is Praxis Coffee Roaster's Esperanza Aquiares, a fermented Costa Rican bean with a light roast.
These are the coffee grounds after a few seconds of stirring. I use a spirograph-type pattern (as suggested to me by coffee guru Jake), and move gradually from the bottom of the basket to the top. I was startled by how incredibly fluffy the grounds became. Not only did all the clumps disappear, but the coffee nearly doubled in volume. This is not at all like the result I was getting with my needles-in-a-wine cork WDT tool, and a significant improvement in both usability and distribution. Particularly impressive is the lack of retained grounds on the needles- my previous tool always retained a small amount of coffee.
This is a video of one of the first pours I recorded after receiving my Ultra WDT. Not perfect, but representative of what my first coffee in the morning looks like when I'm half asleep and in desperate need of caffeine. Anecdotally, the incidence of squirters has dramatically decreased, and my Linea Mini's backplate is much cleaner than it has been since I first got the machine. Since I started using the Ultra WDT tool, I have noticed a huge increase in the consistency of my pulls, with 18.0 grams of coffee yielding 36 grams of espresso within a second or two of my target time, every time.
For those of you who have also received the Ultra WDT tool, what do you think of it? How does it compare to your previous WDT tools?