Okay... I have gotten really good at getting consistent results with my prep routine. I get repeatable and desired results cup to cup from each bag of beans.

Issue is with spurting. Kind of spurting I am getting are not gushers, but small round specs on the cup. I have seen some here say that spurting is not an issue to worry about, and others that say it is something that should be dealt with.

I find that when spurting happens it happens for the entire bag. If my first shot from a bag spurts it will for the entire bag. Espresso tastes fine and timings are fine. I use one roaster where no variety from them spurts, then I have one roaster where all their roast spurt for me, then some where it depends on the bag itself. Unfortunately as of now I have never recorded which roasts spurt, so I can't figure out any pattern at this point.

Anyone else experience this?

I do WDT, rake to level and tamp evenly for a level puck.

What causes spurts that leave a small amount of round dots on the glass? Normal for some bags and not others? If not how does one attack this if the cup tastes fine?

Thanks!

Ken

Unless you have your cup right up next to the portafilter, then you would expect some spurts to also be outside the cup and on your machine, if you had a problem. Does your machine show any signs that you are getting some spurting outside the cup, onto the machine? If not, then it could simply be some random splashes of liquid in the cup as it's filling up. Maybe that specific roast you are using results in a thinner liquid, so more prone to splashes?

Thanks Alan,

Definitely not splashes, spurts that a few do make it outside the cup.

Ken

Ken, This is happening with a naked portafilter, not a spouted one, right? If so, it's kind of normal, although, I must confess that I've never attributed spurting to a particular batch of coffee (I roast all my own and have for years, so can't comment on "per bag"). Personally, I view the naked portafilter as a diagnostic device, not a production device. So, if you're happy with the coffee and have your routine down pat, why not switch back to a spouted PF, which will eliminate spurting.

Edit: Oops I didn't look at your equipment list. No spouts worth using.

I have a robot, so the spouts are not really worth using. First off it is a big and heavy heat sink, but most important is that there is very little headroom with the robot, especially if using a scale. There are some cups that are short enough to get in if you tilt the cup in.

It is weird with the per bag issue. All bags from B&W roasters gave me spurts, I am currently using George Howell beans and this depends on the particular bag. I found a fairly local roaster to me that I really like, and so far I have used 7 bags with no spurts at all.

If it is normal I can live with it. I was just wondering if perhaps a certain roast level or origin needed special treatment, and if so what that would be.

Likely the grinder is creating a fair number of particles that interface just so with the basket holes coupled with minimal channeling and / or unven lever pressure.

Try grinding slightly coarser / dose slightly higher [¼g]. If that solves the issue, good. If it's worse try the same increment in the opposite direction.

Thanks Ian, I will give that a try. Will report back after trying it for a while.