I owned a Oscar for about a year. Made some very good shots. About 3 weeks ago I got a Vivaldi. While I can make some good shots I'm consistently getting donut extractions using the Stockfleths technique. I have heavily resisted going to WDT in order to try to avoid spending 4 minutes per shot. Well I bit the bullet and, yup, WDT solved the donuts. Now the question is, how the heck do I learn how to do it like a pro while avoiding the donuts?

the setup and techniques I've tried so far:
Baratza Vario
Beans - always between 4 and 10 days, Verve, Sightglass, De La Paz, 4 Barrel, Black Cat
16-20 grams in double and triple baskets in a bottomless portafilter
tap a few times during the grind, one tap on a surface after the grind
nutating and straight tamp
Chris King flat tamper

thanks in advance.

I normally use 14-15gram doses in my Vivaldi. Try dosing a little bit less. Also, are you using a straight tamper? The word is the Vivaldi likes a curved tamper, which is what I use. With smaller doses and the curved tamper, donut extractions are never my issue.

Good luck

I agree with Allen, lower the dose. If the puck crashes against the dispersion screen on lock-in, channeling is sure to follow.

Also keep in mind that the Stockfleths Move is a redistribution technique. The Baratza Vario mets out coffee slowly enough that you should be able to distributed the coffee evenly across the basket by rotating the portafilter as it fills. If done correctly, there is minimal need to correct the distribution via the Stockfleths Move (= minor corrections) or WDT (= major corrections).

As a side note, your donut extraction may also come from your different basket and your tapping twice the ground.
Baskets that curve at the bottom (like faema, synesso..) do well with the tap and center tamp, but La Marzocco and some other's do not. I don't know about the vivaldi though.

In no particular order:
Yup, WDT and Stockfleth. First time I've written those.

I typically move the portafilter around during the grinding or shake it back and forth gently a little to help do the initial distribution. The grinds coming out are light and fluffy. I've also tried doing it without tapping.

The baskets are flat bottomed.

I'll try a lower dose. Sounds like that might be the culprit. ~16-17 grams would have the grinds to the top of the basket. If I do ~14-15 grams, without a doubt I wouldn't be able to do a Stockfleth distribution since the grinds wouldn't extend over the top of the double basket. I've also read that some people can get away without even doing that minor distribution.

Ok, time to go play. I'll report back on how it's going.
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just posted that and tried it but only on two shots. 15 grams had the unpacked coffee to the edge of the double basket. I'll keep trying and report back. I'll also try the triple basket with ~18g of coffee.


thanks for your help.

With my B-Vario I would split the dose in half. So, if you need 10.4 seconds for your full dose I would split that in half and use two 5.2 second doses. After the first half, I would shake the PF, and then one light tap on the mat to get the grounds to flatten / settle. Then, after the second half is in the basket I just do a nutate and light tamp. Works well.

With the Vivaldi, IMO, if you fill the basket enough to level the top in any way, there is a very good chance that your puck is going to make contact with the screen when its put back in the group. There is less than average head room on the Vivaldis.

Looks like 15g or less was the key. Still seems strange dosing so little when I was used to 18-20g with a 58mm portafilter but the proof is in the cup.

thanks everyone.

I have your exact same setup, Vario and Vivaldi. I have always used WDT in part as a sure fire way to make sure the grounds ended up in the portafilter. If I had to guess it might add about 12-15 seconds to making a shot (2 seconds to put the cup-top in the portafilter, about 10 seconds of stirring and another second or two to take it off). In your initial post you were concerned about taking additional time, but I consider those 15 seconds some of the most valuable in my prep time! Don't worry about "doing it like a pro", that is the great luxury of being a home-barista...you are not trying to set any land speed records, you are (or should be) just trying to make great coffee.

HB wrote:The Baratza Vario mets out coffee slowly enough that you should be able to distributed the coffee evenly across the basket by rotating the portafilter as it fills.

How exactly would you do that?