Metal Mesh Cone Filter
How to brew with a reusable metal cone filter like the Able Kone for Chemex: how it works, the grind debate, sediment, cleaning and its 2011 Portland origins.
Contents
- Method
- The short version
- How does a metal cone filter work?
- What grind should I use with a metal filter?
- How do you use a metal cone filter, step by step?
- Why is my metal filter coffee muddy or slow?
- Which metal cone filter fits which brewer?
- A short history of the Kone
- Metal cone filter vs other methods
- Words in this guide
- Questions & answers
How do you use a reusable metal cone filter?
Sit the metal cone in your brewer, such as an Able Kone in a Chemex, add ground coffee and pour hot water gently over it, then lift the filter out and rinse it. With no paper, more oils reach the cup. Grind advice differs: Ratio suggests slightly coarser than for paper, while Able’s founder has argued for finer.
At a glance
- Difficulty
- Beginner
- Origin
- Global & Modern
Method
Seat the filter
Sit the metal cone in your brewer. The Able Kone fits 6, 8 and 10 cup Chemex brewers and the Ratio Glass Carafe.
Add the coffee
Add your ground coffee. Sources disagree on grind, so start near your usual pour-over grind and adjust.
Pour gently
Pour hot water slowly and gently over the coffee, so the grounds settle into a bed that helps filter the brew.
Let it drain
Let the water drain through. If it backs up, go coarser next time. If the cup is silty, try a gentler pour or a different grind.
Rinse the filter
Lift out the filter, knock out the grounds and rinse it. Able says to simply rinse and repeat.
A metal mesh cone filter is a reusable stainless steel filter that replaces paper in a pour-over brewer. The best-known is the Able Kone, designed in Portland, Oregon, for the Chemex, with a smaller Kone Mini for the V60. With no paper to trap the oils, it makes a fuller-bodied cup, and there’s nothing to throw away. Here’s how it works, how to brew with one, and the grind question people disagree on.
The short version
- Reusable: perforated stainless steel instead of paper. Rinse and reuse.
- Fuller body: more coffee oils reach the cup than with paper.
- The Able Kone fits 6, 8 and 10 cup Chemex brewers. The Kone Mini fits the Hario V60.
- Grind is debated: Ratio says slightly coarser than paper, Able’s founder has argued finer.
- Pour gently so fine particles don’t get pushed through the holes.
How does a metal cone filter work?
Paper filters trap fine particles and most of the coffee’s oils. A metal filter has holes instead, so more oil and some very fine particles pass through. That’s where the heavier body comes from, and also the risk of a little sediment.
Able describes the Kone’s construction in detail:
- One piece of precision-welded, photo chemically etched stainless steel, with an injection-moulded, food-safe polymer support ring.
- A square-to-round hole design, which Able says reduces clogging and gives an even flow through the grounds.
- Polished stainless steel, which Able says imparts no flavour and resists build-up of coffee oils that can turn rancid and bitter.
The Kone Mini adds a graduated density hole pattern, which Able says suits both small brews and larger batches. The Kone also comes in a black titanium-coated version.
What grind should I use with a metal filter?
This is where sources genuinely disagree:
| View | Who says it | Why |
|---|---|---|
| Slightly coarser than paper | Ratio Coffee | Fine coffee can clog the holes and cause overflow. Your paper grind may let small solids into the cup |
| Finer, with gentle pouring | Keith Gehrke, Able’s founder, quoted by Oil Slick Coffee | “With reusable filters, the goal is to clog the filters”, so the coffee bed becomes the filter and holds back fines |
Gehrke’s point is that turbulence is the real enemy: pour too hard and you force fine particles out through the holes, “because no hole can stop them”. Ratio’s point is practical: too fine and the brewer backs up.
I’d start near your usual pour-over grind and adjust. If it drains too slowly or overflows, go coarser. If the cup is silty, pour more gently first, then try changing the grind.
How do you use a metal cone filter, step by step?
- Seat the filter in your brewer, such as a Kone in a Chemex.
- Add your ground coffee and level the bed.
- Pour gently, keeping the flow low so the grounds settle into a filtering bed.
- Let it drain through.
- Lift out the filter, knock out the grounds and rinse it.
Able doesn’t publish a fixed dose on its product pages, so use your normal pour-over recipe as a starting point and adjust by taste.
Why is my metal filter coffee muddy or slow?
| Problem | Likely cause | Try |
|---|---|---|
| Silt or sediment in the cup | Fines pushed through the holes | Pour more gently, or try a slightly coarser grind (Ratio) |
| Very slow drawdown or overflow | Grind too fine, clogging the holes | Go a little coarser (Ratio) |
| Coffee tastes stale or bitter | Old oils building up on the filter | Rinse after every brew and keep the steel clean |
Which metal cone filter fits which brewer?
| Filter | Fits |
|---|---|
| Able Kone | Chemex 6, 8 and 10 cup, Ratio Glass Carafe, and Ratio Eight, Technivorm Moccamaster and Bonavita drip brewers (Able) |
| Able Kone Mini | Hario V60 (Able) |
Able’s filters are designed in Portland and, Able says, assembled in China.
A short history of the Kone
Able tells its origin story simply: the founders ran out of paper filters for their Chemex one morning, couldn’t find a reusable filter that fitted its shape well, and sketched their own on the kitchen table.
- The Coava Kone: Oil Slick Coffee says Keith Gehrke first made the Kone with Coava Coffee in Portland, as the Coava Kone.
- 2011: Able says the Kone, designed by Gehrke, made its debut at Coava Coffee’s brew bar in Portland, Oregon.
- Able Brewing: after Gehrke and Coava parted ways, Oil Slick says he continued the design under Able, adding a flat tip, a rigid black ring and a new hole pattern.
- Today: Able says its reusable filters are used in homes, cafés and competitions around the world.
Metal cone filter vs other methods
- Chemex: the brewer the Kone was made for, usually with thick paper filters.
- V60: the cone the Kone Mini fits.
- French press: another metal-filter brew, by immersion.
- Cloth bag pour-over: a reusable cloth filter, between paper and metal.
- Ceramic cone pour-over: the classic paper-filter cone.
Explore every pour-over in the pour-over chapter.
What you’ll need
Words in this guide
- Metal filter
- A metal filter is a fine stainless-steel mesh that holds back coffee grounds, as used in a French press plunger and some reusable pour-over filters.
- Pour-over
- Pour-over is a way of making filter coffee by hand: you pour hot water over ground coffee in a filter cone and let it drip through into a cup or jug.
- Body
- Body is how heavy and textured coffee feels in your mouth, from light and tea-like to thick and syrupy.
- Fines
- Fines are the very small, dust-like particles that every grinder produces alongside the main grind.
- Drawdown
- Drawdown is the final stage of a pour-over brew, when you have stopped pouring and the remaining water drains through the coffee bed.
- Immersion vs percolation
- Immersion brewing steeps all the coffee in all the water at once, as a French press does.
Questions & answers
What is a metal cone coffee filter?
A reusable cone of perforated stainless steel that replaces a paper filter in a pour-over brewer. The best-known is the Able Kone, made for the Chemex. Able describes it as photo chemically etched stainless steel with a polymer support ring, which you rinse and reuse instead of throwing away.
What grind should I use with a metal cone filter?
Sources disagree. Ratio Coffee says Able filters work better with a slightly coarser grind than paper, because fine coffee can clog the holes. Able founder Keith Gehrke has argued for grinding finer and pouring gently, so the coffee bed itself becomes the filter. Start near your usual grind and adjust.
Why does my metal filter coffee have sediment?
Metal holes let more fine particles through than paper. Ratio Coffee says using your paper-filter grind with a Kone can leave small coffee solids in the cup, and suggests a slightly coarser grind for a cleaner result. Keith Gehrke says gentle pouring stops turbulence forcing fines through the holes.
Does a metal filter change the taste of coffee?
Yes, it usually gives a fuller-bodied cup. Able says the Kone brews coffee "rich with oils and flavors normally trapped by paper filtration", and that its polished stainless steel imparts no unwanted flavour. Expect more body and a little more texture than paper.
Does the Able Kone fit my Chemex?
Able says the Kone fits 6, 8 and 10 cup Chemex brewers and the Ratio Glass Carafe, and also fits Ratio Eight, Technivorm Moccamaster and Bonavita automatic drip brewers. The smaller Kone Mini is made for the Hario V60.
How do you clean a metal coffee filter?
Knock out the grounds and rinse it after every brew. Able’s instructions are simply to rinse and repeat, and it says the polished steel resists the build-up of coffee oils, which can turn rancid and bitter.
Sources
- Kone: Reusable Filter for Chemex. Able Brewing
- About Able. Able Brewing
- Kone Mini: Filter for Hario V60. Able Brewing
- Able Kone troubleshooting. Ratio Coffee
- Kone From Able Brewing. Oil Slick Coffee
General guidance only. Not medical, food-safety or professional advice. Always follow your equipment's own instructions.