I love the physical characteristics of springs...
The force required to compress a spring is proportional to the amount that it is compressed... it's a beautiful thing. You may have read my praise of spring lever espresso machines, and now I'm going to write about the beauty of a spring in your espresso set up in a completely different context.
Sworksdesign produces an amazing stepdown billet basket (here's one of my blog posts on it) that I use every day to produce tasty espresso shots. I was looking through the packaging and discovered a "dynamic shower screen assist spring". One places a puck screen on top of a tamped coffee filter basket and then further places a spring (as pictured above) on top of the puck screen. As the puck saturates and expands, the spring increases back pressure on the puck (in proportion to the amount of expansion). This allows for coarser grinding (all the rage right now) and also deals with sloppy puck syndrome... the pucks that come out of this process are super tight as you can see below.
Before using the dynamic shower screen assist spring:
After using the dynamic shower screen assist spring:
The shots themselves are more delicious than ever! Quite the rabbit warren. I'll write a subsequent blog post about chasing my own tail on espresso extraction soon!
PUBLIC SERVICE ANNOUNCEMENT: WE'LL BE TAKING A ONE WEEK BREAK BETWEEN JULY 20 AND JULY 27 INCLUSIVE... LAST ROASTING DATE BEFORE THEN WILL BE FRIDAY JULY 18 AND WE WILL RESTART ROASTING MONDAY JULY 28
To read a primer on espresso extraction click here
To read about pre-ground versus freshly ground coffee click here