1. The picture of your shot doesn't show evidence of over-extraction.

2. Because your Baby can't be temped accurately or consistently; because the pump pressure can't be regulated to deliver consistent pressure of ~9bar; and because of some of its other characteristics, there are limits to what you can confidently diagnose and then tweak. Given the machine's capabilities, there's only so far that technique can take you before luck kicks in.

3. 30g extraction from an 18g shot in 30 seconds suggests too much pressure, and (assuming the temp isn't too high) an over-cranked pump implies under rather than over-extraction to me. But I'm not great at making inferential diagnostics.

BDL

HB wrote:An easy way of sharpening your taste vocabulary is pulling a shot at the extremes.

For example, a 10 second gusher espresso should be sour / dull. A 60+ second near choke should taste very harsh / bitter. Try adding 10 seconds to the first pour time by tightening the grind setting and subtracting 10 seconds from the second pour time by loosening the grind setting. Beginners often make the mistake of sneaking up to a problem in tiny steps; try deliberately overshooting the target by a wide margin and then ~halving the difference. You'll be within the sweet spot in less than 4-6 pulls (or at least understand how pour time and grind setting impacts flavor).

This is a great suggestion. I have some 16 day old coffee that's beyond its prime. I'll use it up this way.

boar_d_laze wrote:

2. Because your Baby can't be temped accurately or consistently; because the pump pressure can't be regulated to deliver consistent pressure of ~9bar; and because of some of its other characteristics, there are limits to what you can confidently diagnose and then tweak. Given that the machine's capabilities, there's only so far that technique can take you before luck kicks in.

BDL

From what I understand, the machine is tuned for ESE pods, so it's putting out 12-13bar. Annoying that I can't modify that without a major mod. To combat this, am I right to assume I need to grind finer than typically to hold back the stronger pressure?

boar_d_laze wrote:

3. 30g extraction from an 18g shot in 30 seconds suggests too much pressure, and (assuming the temp isn't too high) an over-cranked pump implies under rather than over-extraction to me. But I'm not great at making inferential diagnostics.

BDL

Wouldn't too much pressure on the puck cause it to flow out faster?

MikePriz wrote:Wouldn't too much pressure on the puck cause it to flow out faster?

You'd think; but no, it's the other way around. In a vibratory pump system -- up to the pump's limit -- the greater the load the greater the pressure.

BDL