Umikot
WDT is an art. Its chaotic nature takes skill to master consistently.
Umikot is a Tagalog word which means: to spin; to turn around; to revolve; to rotate; to circle; to go around; to swirl; to gyrate.
In that spirit, this open-source, 3D printable, spirographic WDT tool utilizes a print-in-place planetary gear mechanism to create spirographic needle motion. Versions are available for 58mm and 54mm baskets.
A heart-warming call-out from John Weiss, the creator of the Weiss Distribution Technique, on the Decent Espresso owners Basecamp!
Thank you, John!
A common problem with many commercially available WDT tools is that they utilize concentric motion, which creates trenches in the coffee. Umikot's spirographic pattern avoids needles crossing the same path, with the goal of a more homogeneous particle distribution.
I have optimized the needle pattern for even coverage, and no more than 8 rotations of the handle should be necessary. Two different needle lengths provide deep and top of the bed distribution.
The needles are inserted from the top and are replaceable, and the base is swappable, allowing for configurable needle depth for different baskets, without needing to change out the needles. Optionally, you can print versions of the base with magnets and/or a flange to interface with the portafilter lugs. A little de-bossed label to indicate a given base's depth is included for easier identification.
Instructions and 3D-printable files can be found on my Printables!
The source is available here on OnShape under a Creative Commons Attribution-NonCommercial-ShareAlike license.
