biketo wrote:Just spitballing, but maybe too much coffee in the basket is causing the leaks, i.e. the puck is mashed against the shower screen before a complete seal is established at the group gasket. Your description of flow suggests too fine a grind with some distribution issues that eventually lead to channeling. Make your grind a little coarser until you are down to 5-7 seconds to first drop and stir with a toothpick before you tamp to distribute the grounds more evenly.
nuketopia wrote:Sounds like several problems going on.
First, the leaking issue. Clean your brewhead and especially the gasket. If you have a blind flush basket, use it to troubleshoot the issue. You may just need a new gasket. It is common to replace these 1-2 times a year in a home, far more frequently in commercial service.
This "nothing to gushing" problem indicates a grind or bean problem. Stale beans will do this in the best of circumstances. In that case, the only cure is freshly roasted beans.
Grinding issues also cause the problem. If the grinder is not producing uniform particles and is set fine, the first flow will be slow from the fine grinds, then channeling takes over and the water breaks through the coarser parts and starts gushing. Try grinding coarser. Once you eliminate all other causes, you may just need to service or replace the grinder with something better.
nuketopia wrote:The grinder is the most critical bit of equipment in the chain. I understand the budget constraints. I think Sette 270 is about $150 more than the Breville. The new Sette AP is only $50 more, but I don't know much about it.
The Sette 270 will definitely produce a good espresso grind.