The double basket the espresso runs through
The filter basket is the basket that sits in the portafilter and holds the ground coffee. The water leaves the puck through the fine holes in its base – and because this happens on just a few square centimetres and under pressure, the condition of these holes helps decide how evenly a shot runs. This basket is designed for around 14 grams, the measure for a double shot.
That is exactly why a basket is a wear part and not a part for life. Coffee oils and limescale build up in the holes, first in individual spots, then unevenly across the whole surface. The water looks for the open path, the puck is washed out on one side and stays wet on the other – without anything having been changed in the grind size or dose.
Descale first, then replace
Before a basket is replaced, it should be degreased and descaled. If you put the removed basket into Puly Caff Plus cleaning powder and, with hard water, follow up with descaler for E61 and BZ groups, you will recover a surprising share of the flow – a basket that then lets water through evenly again was not worn but clogged. Suitable products are in machine and grinder cleaning. Replacement is only worthwhile if the holes stay blocked even after this treatment or the rim is mechanically damaged.
When it's due
The shot runs unevenly: at one spot it shoots through, while the rest of the puck barely sees any water. The time to the first drop varies from shot to shot, even though grind size and dose stay the same. Individual holes are visibly blocked when held up to the light. The puck no longer knocks out dry. Or the rim of the basket is bent, notched or dented so that it no longer seals cleanly in the group.
At a glance
| Type |
Filter basket for the portafilter |
| Installation location |
in the portafilter |
| Fits |
Rocket portafilters |
| Dose |
around 14 g, a double shot according to the item name |
| Scope of delivery |
one filter basket |
| Version |
Diameter, height, hole pattern and material are not specified in our documents |
| Brand |
Rocket |
Who it's for
For everyone with a Rocket who pulls double shots every day and whose basket no longer lets water through evenly after years of service. Also for workshops that want to rule out the basket when diagnosing channelling before they turn to the grinder and brew group. Nobody can reliably tell from the outside which basket is in your portafilter – send us the model and serial number and we will check it together.
What goes with it
As a single basket we carry the 7 g filter basket. Both baskets belong in Rocket portafilters: for the R8 and R9 in the single portafilter for R8 and R9 and the double portafilter for R8 and R9, for the R9 ONE in the single portafilter for the R9 ONE and the double portafilter for the R9 ONE, for the Appartamento TCA in the TCA single portafilter and the TCA double portafilter, plus the two portafilters single portafilter complete and double portafilter complete. Without a bottom, there is the bottomless portafilter with double basket, which already comes with its own double basket.
The portafilter cap sits on the handle. In the brew group behind it are the flange gasket for the brew group, the fine filter for the brew group and the brew group shower screen. For backflushing you need the blind filter. More parts are in the service parts and in Rocket accessories and spare parts.
From our workshop in Bern and Zurich
We take the basket out at every service and hold it up to the light. Whatever remains as a dark spot goes into cleaning powder overnight, and only the next morning do we decide on replacement. That is our order of steps in Bern and Zurich, not a manufacturer's instruction. For the test shot afterwards we use Cozy Chocolate or Nutty Delight, and for maximum body without acidity Very Nutty. More in our coffee beans.
Returns excluded
Service parts are excluded from exchange and return. They are procured specifically for your order and cannot be resold after installation or a test fit on the machine. So before ordering, check the model, year of manufacture and serial number of your machine – or drop us a line and we will clarify the fit together. Your rights in the event of defective goods remain unaffected.
Frequently asked questions
How much ground coffee is this basket designed for?
The item name states around 14 grams, i.e. a double shot. Our documents do not give an exact capacity in grams or millilitres.
Does it fit every Rocket portafilter?
Our documents list it as a filter basket for the Rocket portafilter, without a list of series. Send us the model and serial number of your machine and we will check the fit before you order.
Is there a part number for this basket?
No. Neither our item documents nor the catalogue give a part number for this basket, and we will not make one up here. If you have a number from service documentation, send it to us and we will compare.
Is cleaning worth it instead of replacing?
Almost always as a first step. A basket that lets water through evenly again after cleaning powder and descaler was clogged, not worn. It is replaced if the holes stay blocked or the rim is damaged.
Can I see the part in your showroom?
Yes. We are in Bern at Gerberngasse 44 and in Zurich at Hagenholzstrasse 50b. Let us know shortly beforehand and we will have the part ready.
Questions about the fit? Write to us at [email protected]. We deliver across Switzerland and to Liechtenstein in 2-4 working days.
