Ordered a .1 gr scale for dosing. Thanks for all the feedback. Randy G. your site is very informative.

Randy G. wrote: See. I was right. It did take a whole website.. But read my article and use it as a long-term reference guide: 12 - EASY GUIDE TO BETTER ESPRESSO AT HOME. It will help.

Nice site, thanks for that! The only worry about experimenting more and reading less is the fact I have already wasted some precious grams of expensive coffee doing s**** lol but surely practice makes it perfect.

Randy G. wrote:On my E-61 just this morning I went from 16.2 to 16.4 grams and set the grinder just a little more coarse than it was. Made a HUGE difference in the cup. ... Small changes can make a big difference. ... I might try 16.5 grams tomorrow!

Per Wikipedia: "Chaos theory is the field of study in mathematics that studies the behavior and condition of dynamical systems that are highly sensitive to initial conditions". So... is espresso a dynamical system? Some parts of it (e.g., turbulence) are clearly chaotic in nature, but overall, I don't think so. Do small changes really lead to huge differences? Not in my experience. I generally find that small changes cause small differences, and big changes cause bigger differences.

Different coffee beans (or roast levels) and grind settings generally produce big changes. But a tenth of a gram difference in dose - essentially one coffee bean, well under 1% of the dose - is unlikely to have a noticeable impact on your extractions. To observe the impact of dose, you need to make significant changes. For dialing in a new E61 HX box, I would suggest 16g->17g->18g, backing up by 0.5g when you've gone too far.