Sunday 7 August 2011

67 Cremina - Pulling the first few shots

The machine is now fully restored and sitting on the kitchen counter across from my Vivaldi. Time to pull a few shots.



The first one I pulled before the restoration was much too hot, so I dropped down the pstat to somewhere near midway as my starting point.

I turned on the machine and everything seemed to be holding together well. Only a small leak from the nut on the top rail holding on the steam faucet. For some reason a new copper washer was left out of my rebuild kit from OE. I needed to re-use the old one, but these are only one time use items. (By the way, I e-mailed OE and Barb sent me a new one in the mail right away...aren't they great!).

The machine warms up quickly (only 6 minutes until the heating light goes off!). I bled off the false pressure from the steam wand and then did 3 flushes with the lever to warm the grouphead. Only 8 minutes from on, and I'm ready to make a shot....amazing. (For comparison, my Vivaldi takes 40 minutes to get up to temp and stable). This is the fastest warming machine I've ever used, truly a "walk-up espresso" lover's dream machine!

I then ground 16g of Vermont Artisan Coffee "Espresso Blend" that was roasted 4 days ago (I picked it up myself from the roaster a few days before when I was at the Vermont roasting facility). I pulled my first shot, but it was cold and sour. Obviously I had gone too far in lowering the pstat.

I knew this machine would take some time to calibrate to the proper temperature. It involves quite a few subtle variables like warm-up time, number of warming shots, number of previous shots, etc. A moving target that would require me to gain experience first.

Luckily, I have a big advantage here in that I have a super accurate and consitant LaSpaziale Vivaldi sitting across from Ms. Cremina. So all it takes is to warm 2 cups on top of the Vivaldi, pull one shot from the Vivaldi, and a second from the Cremina. I then compare espresso temperatures (in the cup), with my probe digital thermometer, and I should be bang on. When set to a group temperature of 93F, the Vivaldi gives me a perfect 66C in the cup. So this is what I aim for on the Cremina. It only took 3 shots (3 seperate days actually), and after raising the psat about 5 turns higher, I was dialed in at 66C.

I attached my OE steam wand Omega pressure gauge and measured a pressure swinging from 0.8 bar to 0.95 bar. Seems good to me (from what I've read). I also read Olympia recommends 0.9 Bar.

So here's the current espresso shot process (using my Mazzer SJ grinder). Enjoy!



No comments:

Post a Comment