Shot diagnosis - patchy naked portafilter - images inside - Page 2

Beginner and pro baristas share tips and tricks for making espresso.
_Ryan_ (original poster)

#11: Post by _Ryan_ (original poster) »

cafeIKE wrote:How much coffee in the basket and how much yield?
How tall is the IMS screen?
20g in, 30g out. (1:1.5)

IMS screen:

Body diameter: 56,5 mm
Border diameter: 60 mm
Wall height: 17 mm external
Perforations: Ø 3 mm, 98 holes
Distribution: Circular

It's their 200um e61 model.
cafeIKE wrote: If you lock in the pf with a US nickel sized coin, ≈20 x 2 mm, and then remove, how big an imprint does it make?
Aussie 10 cent coin is 2mm thick. With a 20g dose in a VST 20g basket, no imprint.
cafeIKE wrote: The middle position is a ZERO-pressure coffee soak, not pre-infusion. It's uncontrolled, non-repeatable and IMO, a FWoT.
Pre-infusion was the rationale behind the e61 design.

e61's make great espresso with a practiced hand on the controls. They don't make the same espresso as a Slayer or GS3 or Decent or Verve or any lever, but they certainly hold their own. For cruising, it's hard to beat a '61 Bonneville Convertible. Gimme that any day over any current plasti-fab!
Noted. Was just trying something different with the soak. Not my standard.
cafeIKE wrote: Aim for an even 'bloom' on the basket, regardless of dose. The cone should center within a few seconds. Only when making uber-ristretti are multiple cones permitted, but the basket should have no blank spots.
I generally get even bloom/seep/basket penetration. The blank spots is what I'm chasing and had assumed are a technique issue, but upon reflection it does seem to trend with beans.

_Ryan_ (original poster)

#12: Post by _Ryan_ (original poster) »

exidrion wrote:Then why drive yourself nuts and obsess over a good looking extraction? Is this not the end goal?
Assumed technique issues, so if there is room to improve, I rather improve.

_Ryan_ (original poster)

#13: Post by _Ryan_ (original poster) »

Jeff wrote:Others may disagree, but that looks a lot like what I'd expect from a medium or medium-light SO.

Those gloppy shots of years past were generally with medium-dark or darker roasts, many times with a robusta blend. Lots of ways to get a pretty shot. Pure luck or the exceptional blending and roasting skills of a master Italian to get one that tastes as good as it looked.
I tried a different roaster that has been on my "to try" list for a while, little darker Brazilian SO(still medium from what I've seen on here), 12 days post-roast.
The visual results add weight to your theory that the roast influences the cone/prettiness.

This was of the second shot, ran out of time to dial it in (probably one adjustment off).

Targeting 1:1.5 for my second shot (first was 1:2.5 and it was sh**. Third will be approx. 1:1.8)
20.1g in (on-demand timer fluke), 30.1g out (by feel, weighed after shot ;) ) - Whilst it hit my targets in a little longer than usual, palate says I need to go coarser for this bean.

- Grind/dose
- Weigh
- Tamp
- Extract
- Weigh
- Sample

First seep

I'll play with this bean some more and maybe try another medium roast (or anything darker than what my usuals have been putting out) to see if it's just bean selection rather than technique.
Pursuing technique improvement is one thing, but if what I'm chasing is actually due to beans probably best to let it rest. :?

User avatar
Supporter ★

#14: Post by cafeIKE »

Questions on the MME:
Do you single dose the grinder?
How much is retained if not single dosed and do you purge for ≈2s before the next shot?
How locked is the grind? IOW, does the set point creep at all?

What happens if you use 19.7g and 1/3 of a grinder tooth finer?

To group:
What mechanism in roast level and SO causes uneven basket flow? As they say, "It's news to me."

_Ryan_ (original poster)

#15: Post by _Ryan_ (original poster) »

cafeIKE wrote:Questions on the MME:
Do you single dose the grinder?
How much is retained if not single dosed and do you purge for ≈2s before the next shot?
How locked is the grind? IOW, does the set point creep at all?

What happens if you use 19.7g and 1/3 of a grinder tooth finer?
No, on-demand grinder, maintain 80-250g in the hopper generally(40-60g consumption per day this week as I'm enjoying my v60 too, many weeks it's 80-100g/day).
Purge ~2s before first shot of the day (approx. 2g), I believe retention is ~1-1.5g but have not verified.
I don't purge between consecutive shots in a 'session'.
Grind set point doesn't creep.

19.5g and same grind nets same behavior.
19g and slightly finer, with other beans, has still resulted in a patchy PF when 20g has resulted in a patchy PF.
Same dose and 2/3 a tooth coarser results in a big swing in extraction on this current bean (from 1:1.5 to 1:2.5)

I'll try your suggested dose/grind experiment in the morning, thanks for the suggestion.


#16: Post by El_hondero »

I have the same issue with ims nanotech baskets

_Ryan_ (original poster)

#17: Post by _Ryan_ (original poster) » replying to El_hondero »

Tried my VBM basket, issue followed the bean used rather than the basket.

_Ryan_ (original poster)

#18: Post by _Ryan_ (original poster) »

Tried some other beans and the issues are common to one bean in particular(which i must have had 4kg or so of), I've also tried it as pour-over (v60, 500g+) and found it had a minute longer draw down even after playing with grind (to the point of going coarse enough to compromise taste).
I read somewhere that some Ethiopians produce more fines, I don't know how much truth there is to it, but it could explain the extraction performance and v60 draw downs.

So, it's a bitch to extract if you want pretty extractions. I can go coarser and it still almost looks like it's choking before extracting nicely, but coarser loses some of the magic.

It takes a while to start flowing when dialed for taste, but extracts a perfect 1:1.5 ristretto at the end of it (which interestingly is the roasters recommendation).
It's technically the worst extracting bean I've ever had. It's got the best aroma when grinding and extracting, and a vibrant crema and lovely fruity notes in the cup. Everyone who has tried it compliments it.

I have another KG on the way. We just won't look at the PF. :D

For those interested, it's:
Natural - 100% 74158 variety grown and hand picked at an altitude of 2260-2360 masl in Ethiopia's Sidamo region.

It has me wondering if I'm starting to find the limits of my grinder, or if flow control would let me extract more from it...