zin1953 wrote:A bit hard to do when your machine is plumbed-in . . .

Ah come on, just tack on the cost of a Flojet and accumulator for the class.

So about half a pound through.. found that 16g works better so far, but shots are still very harsh.
Was able to pull off close to 2oz in 25-27sec, but the taste was way off.. putrid lol

Another thing I notice is that on a lot of pucks, after hitting it out into the trash can, I get this:



This tells me that water never made contact with the center area, thereby being overextracted

What can be causing this?

I have been WDTing lately, and it seems to make no difference. It's driving me wild that with all this equipment and have been making spro for about 2 years, still can't pull a good shot.

godlyone wrote:Another thing I notice is that on a lot of pucks, after hitting it out into the trash can, I get this:

wow - I almost never see anything like that - only on the occasional choked shot. I wonder what causes that to happen? Is it possible you dose into a wet or damp basket? Do you fill and tamp the basket alone, or in the portafilter?

godlyone wrote:This tells me that water never made contact with the center area, thereby being overextracted

You can't over-extract if the water doesn't communicate with the coffee. This would be UNDER-extraction and possible a horizontal channeling issue (i.e. lateral lamination layers). Do you rap or tap or twist while you tamp? My suggestion (again) is to tamp once, straight down, no tap no twist. Keep it Simple.

EDIT:

godlyone wrote:200 dollars is kind of steep for an espresso class especially when you don't need to be taught the basics...

And how much have you now spent in time and money and frustration? Taking the class will have you standing next to a very accomplished barista who could surely watch your technique and point out areas for improvement. Seems to me the experience alone would be well worth the money.

No tapping/twisting while tamping.

We tried dosing into both just the basket and basket into portafilter w. clip (no difference)

The basket is definitely dry. I wipe it a bazillion times before dosing into it.

Do you think it could be an issue w. the vibe. pump?

Uneven water flow to puck could be group screen is partially gunked and plugged up. Only way to tell for sure is removing and visually inspection looking through screen. If you aren't religious about flushing group after every shot, water backflushing after every session (even if the session is only one shot), and minimum monthly detergent backflushing, screen can clog up fast. May appear fine on the bottom from the outside, but the holes above the e61 basket screen will block with oils/coffee particles. Leaving a puck in the PF locked in the group to bake exacerbates the problem fast.

We are very picky about cleaning and do a water flush after each and every shot we do a water flush.
We have removed the shower screen and wiped it down. We backflush w. carfiza about every 2 weeks

we NEVER leave the old puck sitting in the group, always throw it out after making a shot

I shot a video showing the technique and extraction and am currently in the process of converting it.. will post it soon

godlyone wrote:We are very picky about cleaning and do a water flush after each and every shot we do a water flush.
We have removed the shower screen and wiped it down. We backflush w. carfiza about every 2 weeks

Did you hold the screen up to a light and look through it after removal and wipe down? I was recently shocked to find a full 1/3 of the holes plugged. Cursory inspection seemed clean, most definitely was not. This was with routine water flush after every shot, couple water only backflushes every session, detergent backflush every couple of weeks. Should also note the my SO of 30 years had forgot and left the PF locked in with spent puck at least once since last detergent backflush and screen removal... Rather than strong long detergent soak to loosen the blockages just installed one of the two new spares had on hand.

Not saying screen blockage is root of your problems. Just a data point that can be easily missed.

Although a crappy pic (hard to hold camera in one hand and screen in other)



shows that it is clean.
Also needed to mention - this is shower screen after 1 shot, before even wiping it

Note: the darkness is because the light I pointed at is recessed so there is the bright area from the bulb and the dimmer areas of the recessed ceiling part

Bummer, seldom as simple as being a machine at fault! Means of the 4M's shot problem most likely the most common, Mano. No offense intended, most of my shot problems are usually Mano related.

So how are the Harar shots pulling today?

I have a thought....(it's lonely - but it's there )
I had a problem once where my machine's pressure gauge was seriously off, reading wrong.

You could confirm the pressure with a portafilter pressure gauge to see if it's accurate (overpressure could cause many of the problems you're seeing). If you don't have the parts handy to construct the PF gauge setup, you could try lowering the pressure a bar (or maybe even two) as a test. Then adjust your grind for a ~25 second 1.75 oz. shot from 18g in your double basket and see if that helps the taste....