WDT and Tamping…

Weber’s blind shaker price is prohibitive but there are much much cheaper made in China choices - I have one and I have always found a blind shaker to help with the distribution. I started doing it before wdt but found the whole process to be too protracted and ended up doing it as an alternative to wdt but after a while since wdt was faster, I stopped using the blind shaker altogether. I should probably break it out just for a change.

So I have been doing some testing with the MHW3bomber shaker vs WDT. I did six tests for each- 3 with a light roast and 3 with a medium roast. The sample size was based on a power analysis of the data by LH, giving a sample size of 5 for 80% power at alpha 0.05. I shook for 15 seconds with the shaker, 18 gm of coffee aiming for a 1:2.5 ratio and a constant flow rate of 2-2.5 ml/s. I experimented on each pair on different days. Also, the pattern was alternate- Shaker first, WDT second on day 1, WDT first and shaker second on day 2, and so on.

Please see the link for the data. Data

There was a highly statistically significant difference between the 2 techniques. Of course, I cannot minimise bias as I performed the test and made the coffee. Another potential source of bias- I optimised the coffee with the shaker first. However, grinding finer or increasing the ratio to extract more did not improve flavour or EY.

MattH I tap the shaker on the counter- this helps with the grinds stuck to the shaker. I use a dosing ring and place the shaker on it. I’ve ignored LH suggestion to drop the grinds from a height. It’s just messy. A quick swirl with the dosing ring in place and the puck is level. I’ve noticed clumping too- it makes absolutely zero difference to the extraction or subjective taste.

Ok … I just received my manufactured in China Blind Shaker, with top cover. When I shake for say 10 seconds and then place on a fairly tall dosing collar and then remove the cover and then lift and rotate the top of the post in small circles, the coffee invariably lands in my basket heaped unevenly to one side. Am I doing something wrong? What is the right technique?

Anyway I then do a very light shallow surface rake with my 0.35mm WDT needles, that evens the bed. Is this Ok? Or is a bottom tap preferable to even things out? Or will a bottom tap just unevenly compress what was an unevenly distribution of grounds? FYI, I stopped bottom tapping a long time ago, as IMHO this introduced a difficult to control puck compression variable that was better controlled through good tamper technique (I use an EazyTamp, which delivers consistent puck compression). I don’t fill my baskets to the point of needing to bottom tap, just to be able to tamp.

Furthermore, while I have only poured 10 shots with the Blind Basket, I noticed consistent gaps on the bottom of my basket (bottomless PTF) as the shot poured, sometimes at the beginning of the shot and sometimes through out the shot. I have not yet started puck inspections, though I did notice the odd top hole on some. We’ll see, but there is clearly some channeling going on.

Now I licked the whole distribution/channeling issue a long long time ago with proper distribution technique, which for me was deep, middle and top WDT with 5 or 6 well spaced 0.35mm needles. It’s no longer an issue for me and I have focused on other things like brew ratios and pressure/flow/temperature profiles and (just as important) finding a decaf coffee I like. Using the Blind Shaker feels like regressing to a time in my espresso journey when channeling was a problem.

Still, with the help of a friend on Basecamp Diaspora, and an Adaptive profile that he had tweaked for a decaf that is similar to mine, I just yesterday morning poured the best two decaf shots I’ve ever made; now I need to see if I can replicate then consistently and also whether the profile can be adapted to other decaf beans, including both tried and true beans, and beans that I had tried and dismissed. And I need to understand more about why that particular profile worked.

The interesting thing is that I had (about 10 shots prior to these two very good shots) started to use RDT and the Blind Shaker. And 20 shots ago started to use an Espresso Parts HQ 14g Ridgeless Double basket. And it is even more interesting that the apparent unevenness of my Blind Basket distribution (clearly visible on the bottom of my PTF) did NOT affect the quality of this very very small shot sample.

Too early/too soon to tell. Many more shots will be needed before I can draw any conclusions, with series that test one variable at a time. But my curiosity is peaked. My best guess is that it was either the shot profile OR the combination of the profile and RDT and the Blind Shaker.

Stay tuned.

In the meantime my faith in decaf and espresso is sufficiently restored to carry on.

I haven’t done many shots with the Blind Shaker (maybe 10), but every shot had some unevenness (ie flow gaps on the bottom of the PTF). I haven’t started inspecting pucks like I did before my WDT technique improved to a point that distribution and channeling ceased to be a concern. Now we are being told that we should throw out everything that every other professional has taught us, and just shake it up and distribution and evenness be darned? Channeling? Who cares?

Alot more study needs to be done by alot of other professionals before we start drinking this particular coolaid.

This being said, LH has stirred up an interesting debate, which may (or may not) change how we approach espresso.  And gained alot of PR and YouTube hits/$ in the process :)

All of this reminds me of a fable about an Emperor 😁