I WDT all the time, but with only five (5) needles of 0.35mm diameter. I’ve tried 0.25 and 0.3 and find that the needles bend together and move the grounds to much. 0.40 also moves the grounds too much. Too many needles (more than 6) moves the grounds too much. Five 0.35mm needles is perfect for me.
I did try NO WDT, with mixed results. As they say, if its not broken …
I’ve since added a top screen (metal not paper). Whereas I had periodic channeling, I now have none. This allows me to focus on other things.
I do however wonder what the impact would be of no WDT, but with the screen. However my WDT works and I have other things to work on.
Now working to determine best top screen thickness. I have a thick Normcore screen, which removes headroom, which helps avoid sloppy pucks. I preheat the screen with steam, to avoid thermal loss.
Just received a thin Shades of Coffee screen. Tried it once and saw abit of puck sloppiness, with 15g medium-dark coffee in a 15g IMS basket. So a thin screen would allow 16g or even 17g in a 15g basket, and no sloppiness, if I chose to go that route.
A thicker screen results in no sloppiness, but limits the dose to 15g in a 15g basket. Maybe 16g at most.
Question: What’s the right amount of headroom? Is the “nickle test” still true or passe? Or does the right amount of headroom result from a basket loaded to + or - 10% of basket rating, with neither sloppiness or the puck sticking to the shower screen? Or?
Note: My pucks never stick to the shower screen anymore, now that I use a top puck screen.