Too Much Coffee

The pour starring at 10 seconds suggests a fine grind, so getting a 30g pour suggests you ran the shot too long.
Going coarser and still getting a similar effect suggests inconsistent distribution. Getting a gush in flow and a split puck also suggests the same.
If your pours are quite show then you are trying to pull risrettos, which are at the underextracted end of the spectrum so can be sour if not done well.

I would try going a little coarser and taking lots of care with distribution and try to get 30g plots in 25 seconds consistently. The normale extraction ratio should give you leavess soureness.
If you have or can get a portafilter with no bottom, you can easily see tamping or distribution issues.

So tomorrow I'll be aiming for 14-15g in, 28-30g out for 25-30 sec. The bottomless portafilter is on my list but it will happen later on because I need to buy a good grinder first. Thanks for the tips!

bronc wrote:So tomorrow I'll be aiming for 14-15g in, 28-30g out for 25-30 sec. The bottomless portafilter is on my list but it will happen later on because I need to buy a good grinder first. Thanks for the tips!

If your basket will take it, try increasing the dose a bit. I find this can give a smoother pull.
Yes it's not a cheap business, the bottomless PF is a very good tool to see any flaws. When you see a gush from channeling you can see why it ruins the shot. I didn't take care the other day, and got a channeling shot which tasted very sour. I used the same beans today taking care and pulled the sweetest shot I've had in ages, that's how much difference it can make!

14in 30g out (removed the drip tray and put a scale under the glass) but forgot to time the shot. The taste was less sour but more bitter. Massive blonding in the end - I think 30g might be too much output. I'll try another one later this time timing the shot.

I tried another shot this time properly timing and weighing and got something rather drinkable - 23g (14*1.65). The flow was pretty good but when I look at the timer - 20sec. Apparently, all my previous shots haven't been weighed correctly. Unfortunately, the roasted beans finished and I don't want to roast any more because I have the Brazil Daterra to finish and after that I'll be away for a week or so. Hopefully, when I get back home I'll have all I need in order to build the Turbo Crazy roaster which should give me more consistent results.