The details
- This answer covers the Dedica EC685. The EC680 shares the same 51mm fitting, and sellers list the same parts for both. Other DeLonghi models with 51mm groups often appear on the same compatibility lists, but verify your exact model name in the listing.
- The stock baskets are dual-wall (pressurized). They force flow through a small exit hole to fake crema and forgive coarse or stale grounds, which caps how good a shot can taste.
- Upgrade path one: keep the stock portafilter and drop in a 51mm single-wall basket sold for the EC680/EC685. Basket depth varies between aftermarket makers, so buy one that names the Dedica rather than a generic 51mm basket, and check owner feedback on whether the portafilter still locks with a full dose.
- Upgrade path two: a 51mm bottomless portafilter made for the Dedica's three-ear group, which usually ships with a single-wall basket. This also lets you watch extraction and diagnose channeling.
- Remove any plastic crema or flow device from the stock portafilter if you stay with it. Single-wall baskets are meant to flow freely.
The grinder requirement
This is where most upgrade attempts fail. A pressurized basket works with almost any grounds. A single-wall basket does not: the coffee bed itself must provide the resistance, which means a uniform fine grind from a burr grinder, freshly roasted beans, and reasonable puck prep. With a blade grinder or supermarket pre-ground coffee, a single-wall basket produces fast, watery, sour shots, and owners then wrongly blame the basket. Sort out the grinder first and the basket second.
What owners actually do
The established Dedica community recipe is: bottomless 51mm portafilter or single-wall basket, a dosing funnel because the 51mm basket is narrow and easy to spill, a WDT tool to break clumps, and a proper 51mm tamper, since the plastic tamper on the machine is sized for the pressurized system. Owners consistently describe the pressurized-to-single-wall swap as a bigger taste difference than any other Dedica modification, and the bottomless view makes dialing in the grind dramatically faster.
The trap to avoid
Two traps. First, diameter alone is not fitment: a 51mm basket must also match the Dedica's basket depth and retention geometry, so buy parts that name the EC680/EC685 explicitly. Second, do not judge the upgrade on your first shots. Every single-wall conversion needs the grind re-dialed from scratch, usually much finer than the pressurized basket wanted. Expect a few sink shots while you find the setting where a double shot runs slow and syrupy rather than gushing through.