IMS Competition Precision Basket 58 mm Convex H26

Get a more precise starting point for your espresso with the IMS Competition B702TCH26E. This filter basket is designed for double espresso portions and combines a cylindrical shape with a convex bottom and 715 precision-manufactured micro-holes.

The basket is 26 mm high and designed for tampers with a diameter of 58 or 58.4 mm. The ridgeless construction provides a smooth exterior without a retention groove.

Convex bottom with centered flow

The B702TCH26E features a slightly curved, convex bottom. This shape directs the finished espresso toward the center of the basket and creates a gathered flow during extraction.

The convex design is developed to:

• Utilize the coffee puck across the entire perforated area

• Concentrate the espresso flow toward the center

• Provide a clear flow in a bottomless portafilter

• Support the drying of the used coffee puck

• Make the puck easier to knock out after brewing

The basket can also be used in compatible spouted portafilters, provided there is sufficient clearance for the height and the curved bottom.

715 precision-manufactured micro-holes

The basket bottom features 715 holes with a diameter of 0.30 mm. The holes are arranged in a hexagonal pattern over a perforated area with a diameter of 49 mm.

As part of the IMS Competition series, the holes are re-laminated and calibrated after perforation. This ensures a consistent hole size and a more stable starting point for espresso extraction.

The precise perforation makes it easier to work systematically with:

• Grind size

• Dosing

• Coffee distribution in the basket

• Brew time

• Yield

• Coffee-to-espresso ratio

A precision basket cannot prevent channeling on its own. A consistent grind size, thorough distribution, and level tamping remain crucial.

Recommended dosing

The optimal amount of coffee depends on the roast level, grind size, and the density of the coffee beans.

IMS specifies the following recommended capacities:

• Dark roast coffee: approx. 17–19 g

• Medium roast coffee: approx. 18.5–21 g

• Light roast coffee: approx. 20.5–23 g

Lightly roasted coffee beans typically have a higher density and therefore occupy less space at the same weight than dark-roasted beans.

These dosages should be used as a starting point. Always check that there is appropriate distance between the tamped coffee puck and the machine's shower screen. An overfilled basket can cause the puck to hit the brew head and affect water distribution.

For 58 and 58.4 mm tampers

IMS specifies the basket for tampers with a diameter of 58 or 58.4 mm.

A close-fitting tamper helps to compress the coffee evenly all the way to the edge of the basket. This reduces the amount of loose coffee along the sides and provides a better opportunity for a uniform puck.

The designation "58 mm" does not automatically mean the basket fits all espresso machines with a 58 mm brew head.

Therefore, check:

• The internal diameter of the portafilter

• The depth of the portafilter

• The 70 mm outer rim of the basket

• The 60 mm body diameter of the basket

• The 26 mm height of the basket

• The portafilter retention spring

It is recommended to compare these measurements with your existing filter basket before ordering.

Ridgeless construction

The basket is ridgeless and therefore has no external retention groove.

The smooth exterior makes the basket easier to insert and remove from the portafilter. How tightly it fits depends on the spring and construction of the portafilter.

A ridgeless basket can still be held securely, but the fit may vary between different portafilters.

Electropolished surface

The B702TCH26E has an electropolished surface. This process reduces microscopic imperfections and creates a smooth and hygienic surface.

The smooth finish makes the basket easier to clean and helps limit the accumulation of coffee oils and fine coffee particles.

The basket also undergoes wet vibro-finishing with ceramic elements as part of IMS’s post-processing.

Suitable for bottomless portafilters

The convex bottom directs the espresso toward the center of the basket, making it particularly well-suited for a bottomless portafilter.

A bottomless portafilter makes it easier to observe:

• Whether the flow starts evenly

• Whether the espresso gathers toward the center

• Whether channeling occurs

• Whether the tamping is uneven

• Whether coffee distribution should be improved

A bottomless portafilter is, however, not necessary to use the basket.

How to achieve a great result

1. Select a starting dose that matches the roast level of the coffee.

2. Distribute the ground coffee evenly in the basket.

3. Use a WDT tool to break up clumps if necessary.

4. Tamp the coffee level with a suitable 58 or 58.4 mm tamper.

5. Check the distance between the coffee puck and the brew head.

6. Brew the espresso and evaluate the flow, time, and taste.

7. Adjust primarily the grind size while keeping the dosage stable.

Feel free to start at the lower end of the recommended dosage range and increase gradually as needed.

Cleaning and maintenance

Knock out the coffee grounds after each brew and rinse the basket thoroughly with warm water. Regularly check that the micro-holes are not clogged by coffee oils or fine coffee particles.

For deep cleaning, the basket can be soaked in a suitable cleaning agent for espresso and coffee equipment. Follow the manufacturer's instructions and rinse the basket thoroughly with clean water afterward.

Avoid using needles, steel brushes, or other sharp tools that could damage or alter the shape of the micro-holes.

Specifications

• Brand: IMS

• Series: Competition Convex

• Model number: B702TCH26E

• Product type: Precision espresso basket

• Capacity: Double espresso / 2 cups

• Height: 26 mm

• Outer rim: 70 mm

• Basket body: 60 mm

• Tamper size: 58–58.4 mm

• Bottom: Convex

• Retention groove: No – ridgeless

• Number of holes: 715

• Hole diameter: 0.30 mm

• Perforated area: 49 mm

• Hole pattern: Hexagonal

• Surface treatment: Electropolished

• Recommended dose, dark roast: 17–19 g

• Recommended dose, medium roast: 18.5–21 g

• Recommended dose, light roast: 20.5–23 g

• Portafilter included: No

• Tamper included: No

The IMS Competition B702TCH26E is an obvious choice for the espresso enthusiast who wants a ridgeless precision basket with a convex bottom, centered flow, and capacity for a standard or larger double espresso.

Frequently asked questions

How much coffee fits in the IMS B702TCH26E?

IMS recommends approximately 17–19 g for dark roast, 18.5–21 g for medium roast, and 20.5–23 g for light roast coffee. The optimal dose also depends on the grind size and coffee density.

Which tamper fits the basket?

The basket is designed for tampers with a diameter of 58 or 58.4 mm. A close-fitting tamper helps compress the coffee evenly all the way to the edge.

Does the basket fit all 58 mm espresso machines?

No. You must also check the basket's outer rim (70 mm), body diameter (60 mm), and height (26 mm). The portafilter must also have clearance for the convex bottom.

What does the convex bottom mean?

The convex bottom is slightly curved and directs the espresso flow toward the center of the basket. The shape is particularly well-suited for use with a bottomless portafilter.

What does "ridgeless" mean?

Ridgeless means the basket has no external retention groove. Instead, the portafilter spring holds the basket against its smooth exterior.

How many holes does the filter basket have?

The basket has 715 precision-manufactured micro-holes with a diameter of 0.30 mm.

Does the IMS basket prevent channeling?

Not on its own. The basket's uniform perforation provides a precise starting point, but proper grind size, dosage, distribution, and level tamping remain crucial.

Can the basket be used in a spouted portafilter?

Yes, if the portafilter has sufficient diameter and depth for the basket's height and convex bottom. Always compare the measurements with your existing filter basket.

Are a portafilter or tamper included?

No. The product consists only of the IMS filter basket. The portafilter, tamper, and other espresso equipment are sold separately.