by ben-ari on Sat Jan 22, 2011 9:33 pm The first shot:
- LM Double Basket
- 21g
- No WDT, Nutation instead
- 9 minute reverse temperature surf
- Vario Grind: Macro - 1, Micro - 7 (I know that this isn't useful for most people since each machine is different
- The shot didn't pull, the grind was too fine
Second Shot
- LM Double Basket
- 20g
- No WDT, Nutation instead
- 9 minute reverse temperature surf
- Vario Grind: Macro - 1, Micro - 14
- Again this didn't pull, the grind was too fine
Third Shot
- LM Double Basket
- 19g
- 9 minute reverse temperature surf
- Grind: Macro - 2, Micro - 8
- Pull Time: 26.5 seconds
- Shot Volume: 1.4oz
- This shot was a bit sour. I think the temperature was too low for this blend. I had determined that after a reverse temperature surf of 9 minutes, the grouphead brew temperature is about 201 degrees F
Fourth Shot
- LM Double Basket
- 20g
- 5 minute reverse temperature surf
- Grind: Macro - 2, Micro - 10
- Pull Time: 31.5 seconds
- Shot Volume: 1.6oz
- This shot was a bit bitter. I think I may have let it brew too long.
Fifth Shot
- LM Double Basket
- 20g
- 5 minute reverse temperature surf
- Grind: macro - 2, micro - 14
- Pull Time: 19 seconds
- Shot Volume: 1.5oz
- I stopped this shot early because it seemed that it was blonding early. This shot was pretty bitter with an awful aftertaste.
After all of these test shots I'm pretty convinced that there is a problem with my brew pressure. Based on tekomino's suggestion:
tekomino wrote:I would not change the OPV without having a way to measure it. It is sure way to drive yourself nuts. It is actually not hard to build the simple pressure gauge. My recommendations is not to change OPV setting without ability to measure it.
I'm not going to mess with the OPV without getting a pressure gauge. I figured out after reading a bunch of forums (this in particular) made me realize that my Silvia stock portafiler's double spout could come off, but it wasn't easy. I put a towel over the spout and used a hammer to hit it and make it turn counter clockwise. Once it got loose, I was able to unscrew it.
What surprised me is how horrible hardware stores in NYC are. I went to three different places, including Home Depot, and nobody knew what a liquid filled pressure gauge is. Even after I showed them pictures, everybody said "Oh, we don't carry that." I'm going to try to find it again tomorrow, but it looks like I may have to order it online.
Does anybody have any recommendations for pressure gauges for the Silvia? I'm hoping that after learning about my Silvia's temperature surfing as well as figuring out what's up with the pressure I will finally be able to pull good shots.
By the way, Tekomino, your post Digital espresso or a way to consistency looks really good. Thanks for sharing it with me.
