Newbie needs help with first shot of espresso

#1: Post by **mm2531** » January 13th, 2023, 4:19 pm

Many of you were kind enough to help me purchase my first machine (Silvano Evo) and first grinder (Niche Zero). I picked up medium-dark coffee beans from a local roaster yesterday - they were roasted a day ago, so as fresh as they can be.

I've read a lot on this forum, and watched many YouTube videos. I purchased a bottomless portafilter, and a VST 18g basket, a WDT tool, and a Normcore 58.5 mm tamper. I calibrated the grinder, and started on a setting of 19. After 6 attempts, I am ready to pull my hair out (if I had any).

I consistently used 18gm of coffee, used the distribution tool, tapped the portafilter on the table a couple of times, and tamped with moderate pressure. The puck looked great. In every case I got way too much output. I kept grinding finer (now down to 12), but still getting close to 1:3.5 in around 25 seconds (this is from the shot timer on the machine that starts counting the moment one pushes the switch).

On some of the attempts, it did not look like there was channeling - everything was coming out nicely in one stream from the center of the basket, but then all of a sudden there would be one spray from the side. So now I am at a total loss - is the output in excess because of channeling, or am I in too fine of a grind causing channeling? The pressure read between 8-9 bars.

On one or two attempts, there did not appear to be channeling, but still got too much output in around 25 seconds.

Any help would be very appreciated. Thanks in advance.

#2: Post by **ira** » January 13th, 2023, 4:42 pm

Grind finer. Do not worry about what people say the grind should be for them. What matters is your machine combination. Go down 3 clicks, if that's not enough go down 3 more. When you've finally gone to far, then start backing up. There is no particular meaning to the numbers when comparing different coffee's and different setups. Common beginner mistake, there is no penalty to going to fine other than you might choke the machine and then just don't remove the basket till the pressure drops which I believe with the Silvano is as soon as you stop the shot and the 3 way valve opens emptying the pressure into the drip tray.

January 13th, 2023, 5:15 pm

Thanks! One other thing I should mention in case it has any bearing, is that the VST 18gm basket is ridgeless and comes out quite easily from the bottomless portafilter. When I was using the Normcore tamper (it has a spring to regulate the pressure), if I pressed it more than moderately, the basket came out along with the tamper. This meant I could only tamp with a light hand - not sure if that caused the channeling. It seems to me that with a 25lb spring, I should be able to press as hard as it would let me without over tamping.

#4: Post by **ira** » January 13th, 2023, 5:22 pm

Tamp pressure is mostly irrelevant, just make sure the puck is even and anything over 5 pounds is likely plenty. I was certainly not tamping more than that when I was last using a manual tamper. Now I use a Force set pretty light.

#5: Post by **mrgnomer** » January 13th, 2023, 6:45 pm

Agree with the advice. Would add distribution in the basket. I find tap to level out the grounds and a WDT to break up clumps and even everything out before the tamp works really well to prevent channeling.

When I first started using a VST the extraction was consistently faster at the same grind and dose of a stock basket. The puck didn't look like there was channeling. When I overdosed by a couple grams with light roasts the extraction settled down and became more consistent.

January 14th, 2023, 12:18 pm

Thanks, everyone. I gave it a few more attempts this morning with better results, but still have questions.

I went back to the stock double basket that came with the Silvano Evo, and reduced dosage to 16.8gm. I am getting better at puck preparation as there doesn't appear to be any channeling issues that I can see from the bottomless portafilter. I had to go down three clicks to 9 on my Niche to get a roughly 1:2 ratio in 32 seconds. First drops were at 6 seconds.

The shot tastes OK, not great. Still bitter for my liking (beans are medium dark). The machine temperature is set to 200 degrees F. I need to get a thin scale to put under the cup so that I can be more precise at stopping the extraction - right now I am stopping based on shot time and watching for the shot to thin out. Not much room under the cup on the Silvano but I am sure Amazon will have something.

A couple questions: any suggestions on what to try to get less bitterness? Also, is it normal for the shot to be lukewarm? For some reason I thought it would be hotter coming out.

#7: Post by **mrgnomer** » January 14th, 2023, 2:42 pm

Reducing the brew temperature and/or brew pressure can help. I haven't done it in a while but you could also cut the extraction by letting the first bit run and the last bit and just collecting the middle. The start tends to be acidic and the finish over extracted.

#8: Post by **cafeIKE** » January 14th, 2023, 3:01 pm

IMO, a VST basket and a fixed dose are your first mistakes.

Assuming you have a standard double basket, USE IT. Grind 16g going finer until you get the desired ratio, then adjust the grind in ±1/3 steps [about as close as you can get on the Niche] and the dose in ±0.1g increments to adjust for taste.

See Espresso 101: How to Adjust Dose and Grind Setting by Taste and Mano Lite: A Short Guide to Dialing in Espresso SOs and Blends

FWIW, I'm currently pulling a medium dark from Equator in Eugene Oregon. 17.2g [17g if Niche not puffed] in an IMS double @ 11 on the Niche. ≈34g in 25s

#9: Post by **mrgnomer** » January 14th, 2023, 4:11 pm

I don't have experience with a Silvano Evo so I don't why the extraction temperature is just warm. From the specs it looks like the Evo is a thermoblock. It heats brew water on demand.

You might try doing a flush with the portafilter and empty basket locked in before prepping the portafilter for an extraction. Anything heavy brass is a heat sink that could heat or cool a shot depending on its temperature. What I do is lock the portafilter with basket into my machine when it's on and when it gets hotter than I can comfortably hold it's good to go. If your portafilter and basket aren't too hot to hold after they've been locked into your idling machine for a while then a pre flushing them locked in should bring them up to temp.