WHITEPAPERv1.0

    AeroSweep

    A workflow tool for chaff removal and optional fines trapping in competition AeroPress brewing

    June 2026
    22 min read
    Brew Supply
    How-to guide

    Use the AeroSweep guide for the physical tray workflow first. Use the whitepaper for the longer reasoning about separation geometry, fines trapping, and prototype evidence.

    Abstract

    Competition AeroPress recipes often specify dose, water temperature, brew time, agitation, pressing, dilution, and endpoint with high precision. Yet some preparation steps remain much less controlled. Chaff removal and fines handling already appear in high-level AeroPress competition recipes, but the physical workflow is often improvised: brewers blow chaff from narrow grinder catch cups, skip fines removal under time pressure, or rely on separate sieving steps that add transfers, tools, and risk.

    AeroSweep addresses this narrow workflow problem. It comes in two versions: AeroSweep Chaff, the base version for chaff removal, and AeroSweep Fines, which adds a printed fines-trapping floor for partial fines trapping and removal during the same step. Both versions move ground coffee from a narrow catch cup onto a wider tray, giving airflow and gentle side-to-side shaking more exposed surface area to work with.

    AeroSweep Fines extends that workflow by using straight, parallel printed ridges to trap some fines as the grounds move across the tray. Prototype testing suggests that the fines-trapping floor can retain approximately 1 to 3 g of fines from a 20 g dose depending on shaking. Further community testing is needed to quantify repeatability across coffees, grinders, users, and routines.

    The tool does not claim that chaff or fines should always be removed. It does not replace a dedicated sieve, classify particles by exact micron size, or guarantee better coffee. Its value is more specific: it makes one preparation choice easier to repeat, compare, and integrate into a time-constrained competition routine. Chaff is the visible problem. Separation geometry is the real variable. AeroSweep makes that separation step wider, faster, and easier to repeat.

    The Existing Problem: Separation Under Competition Conditions

    1.1Chaff and fines removal already exist in competition recipes

    Chaff and fines removal are not abstract concerns imported from another brewing method. They already appear in AeroPress competition recipes. The 2025 World AeroPress Championship winning recipe by Nemo Pop includes grinding slowly, blowing out chaff, and sifting out fines before adding the coffee to the AeroPress chamber [1].

    The broader AeroPress competition archive also includes recipes where fines are treated as a defined preparation variable, including fines in the 100 to 200 micron range [2]. There is also historical precedent for improvised separation tools: Jeff Verellen’s 2014 WAC recipe used a Sowden Softbrew filter to shake out superfines, with some chaff potentially lost in the process [3].

    1.2The problem is not only sensory

    It is easy to frame chaff and fines removal as a taste question, but the first problem AeroSweep addresses is workflow. A brewer can only test chaff and fines removal seriously if the step can be performed with some consistency. If the process changes every time, the sensory result becomes harder to interpret.

    Narrow claim

    AeroSweep does not begin with the claim that removing chaff or fines makes better coffee. It begins with a narrower claim: if a brewer chooses to remove them, that preparation step should be easier to repeat.

    1.3The catch-cup workflow is useful but incomplete

    The common chaff-removal workflow is simple: keep the ground coffee in the grinder catch cup, blow air across the top, and shake or rotate until enough visible chaff leaves. This method is fast and tool-free, but the geometry is poor. Most grinder catch cups expose only a small surface of the ground coffee at once, so much of the chaff remains mixed into the bed until repeated shaking brings it to the surface.

    A catch cup is not wrong. It is simply being asked to do a separation job it was not designed for. For fines removal, the limitation is even clearer. A catch cup does not intentionally trap or remove fines. If the brewer wants fines removal, they usually need another tool, another transfer, and another step.

    1.4The real variable is separation geometry

    The surface-level problem is chaff. The deeper workflow problem is separation geometry: the relationship between ground coffee, exposed surface area, airflow, and agitation. When ground coffee stays in a narrow catch cup, the brewer is working against the shape of the vessel.

    Catch-cup geometry

    • Small exposed surface area
    • Airflow reaches only part of the coffee at once
    • Chaff remains buried unless the grounds are repeatedly shaken
    • Fines removal requires a separate step

    AeroSweep geometry

    • Wider tray exposes more ground coffee to airflow
    • Gentle side-to-side shaking can spread and turn the grounds
    • Chaff reaches the surface more easily
    • AeroSweep Fines can trap some fines during the same step

    From Chaff Removal to Separation Geometry

    2.1Chaff is visible, but its sensory role is not settled

    Many brewers remove chaff because they believe it can contribute papery, drying, bitter, or distracting notes. In a competition setting, that belief is understandable. But the evidence is not uniform. Baratza describes chaff as natural and harmless, arguing that it does not introduce unpleasant flavors or create a meaningful risk to taste, clarity, or brew consistency [4].

    Community discussion still shows that brewers care about it, associating chaff with papery or drying notes even if the effect is disputed [5]. AeroSweep does not depend on the claim that chaff is always harmful. It starts from the narrower reality that some brewers choose to remove it and need a more repeatable way to do so.

    2.2The issue is not only chaff; it is exposure

    Chaff removal depends on exposure. A piece of chaff can only be blown away if airflow reaches it and if it is light enough to separate from the surrounding grounds. If it remains buried inside the coffee bed, it stays in the dose. This is why vessel geometry matters.

    AeroSweep starts with a simple design move: move the grounds out of the narrow catch cup and onto a wider tray. That changes the physical conditions of the step. More of the coffee is exposed. Air can move across a larger surface. More chaff can reach the surface.

    2.3Why the tray remains open during chaff removal

    AeroSweep remains open during the chaff-removal step because the chaff needs somewhere to go. The Bean Sieve lid is used later, during transfer into the AeroPress chamber. It helps contain the prepared grounds while the brewer pours them through the spout into the brewer.

    The sequence is deliberate: open tray for separation, airflow and gentle shaking for chaff removal, lid on for transfer, grounds into the AeroPress chamber. During separation, the grounds are exposed. During transfer, the grounds are contained.

    Fines as a Recipe Variable, Not a Defect

    3.1Fines are not one thing

    “Fines” sounds like a precise category, but in practice the term is used in different ways. It usually refers to the smallest particles in a dose of ground coffee, but the size threshold depends on the grinder, brewing method, and person using the term. Coffee Navigated notes that the role of fines is disputed and that there is no common size definition [7].

    AeroSweep Fines belongs to the practical category, not exact particle classification. It does not classify particles by micron size or isolate every particle below a threshold. Its fines-trapping floor catches part of the smaller material during handling.

    3.2The competition problem is partial removal under time pressure

    Barista Hustle’s discussion of sieving small coffee particles is useful because it takes a nuanced view: removing very small particles can improve some brewed coffees, while hand-sieving is slow and inefficient [6]. That captures the practical problem well. Fines removal can be worth testing, but the workflow can be costly.

    AeroSweep Fines is designed for a different value proposition. It does not aim to remove all fines or to match a dedicated sieve. It aims to trap some fines during the same handling step already used for chaff removal.

    3.3Shake count is a rough control, not a measurement system

    Fellow’s Shimmy support materials make a simple practical point about dedicated sieving: longer shaking collects more fines [8]. AeroSweep Fines is not the same kind of tool, but the handling principle is related. More shaking generally traps more fines, up to the point where the ridges become visibly filled.

    A useful starting point is around 10 gentle side-to-side shakes. That number is not a universal recommendation. It is a practical anchor. The important part is that it can be remembered and repeated, making the preparation step easier to compare across brews.

    What AeroSweep Is and How It Works

    5.1The basic geometry

    AeroSweep is a rectangular tray with rounded corners, raised walls, and a shaped spout. The wider tray gives the ground coffee more exposed surface area than a typical grinder catch cup. The raised walls help keep the grounds contained during gentle shaking, and the spout supports transfer into the AeroPress chamber.

    The rectangular footprint is also practical for 3D printing and transport, and the shape allows the tool to stack with the Brew Supply Bean Sieve.

    5.2AeroSweep Chaff: the base version

    AeroSweep Chaff is the base version for brewers who want to remove chaff but do not want intentional fines trapping. The workflow is simple: grind the coffee, transfer the grounds from the grinder catch cup into AeroSweep Chaff, spread the grounds across the tray, blow air across the grounds while gently shaking side to side, allow visible chaff to leave the open tray, place the Bean Sieve lid on, and transfer the prepared grounds into the AeroPress chamber through the spout.

    5.3AeroSweep Fines: the fines-trapping floor version

    AeroSweep Fines uses the same general tray design but adds a printed fines-trapping floor made from straight, parallel ridges. During gentle side-to-side shaking, some fines can settle into and remain caught between these ridges.

    This is not sieving. A dedicated sieve separates particles by allowing smaller particles to pass through a defined mesh. AeroSweep Fines traps some fines through contact with the ridged floor during handling. That makes it less precise than a dedicated sieve, but faster to integrate into a competition workflow.

    5.4Transfer into the AeroPress chamber and fines recovery

    Once chaff removal and optional fines trapping are complete, the prepared grounds need to enter the AeroPress chamber cleanly. This is where the spout and Bean Sieve lid matter. The transfer is naturally two-handed: one hand holds the AeroPress chamber and the other holds AeroSweep.

    AeroSweep Fines does not require trapped fines to be discarded. Most can be recovered by placing the Bean Sieve lid on AeroSweep Fines and knocking the back of the base firmly several times. Recovery is practical, not perfect, but it gives the brewer more than one recipe state to compare.

    Geometry Claim

    A wider tray makes airflow-based separation easier to execute

    AeroSweep Chaff improves the working surface for chaff removal by exposing more of the grounds at once than a narrow catch cup.

    Workflow Claim

    AeroSweep Fines adds passive fines trapping to the same preparation step

    The printed ridged floor traps some fines during the same airflow and shaking routine instead of requiring a separate sieving workflow.

    AeroSweep as a Dial-In Variable

    6.1The variable is preparation state

    AeroSweep does not make coffee better by default. A coffee can taste better with chaff removed, and it can also taste better with chaff left in. A brewer may prefer the cup with fewer fines, or they may prefer the full grind distribution. The useful variable is preparation state, not “better.”

    A brewer can compare no chaff removal, chaff removal only, chaff removal plus partial fines trapping, different shake counts, trapped fines discarded, or trapped fines mostly recovered and reintroduced. These are physical differences in what enters the AeroPress chamber.

    6.2What becomes repeatable

    AeroSweep does not make the preparation step perfectly controlled. It makes it defined enough to test. The brewer can repeat the tool version used, airflow method, direction of airflow, shaking motion, number of gentle side-to-side shakes, whether the fines-trapping floor is used, whether the ridges are allowed to become visibly filled, whether trapped fines are discarded or mostly recovered, and the transfer method into the AeroPress chamber.

    6.3What AeroSweep helps brewers compare

    AeroSweep is especially useful when the brewer is running structured comparisons. It can help isolate catch-cup chaff removal versus AeroSweep Chaff, no chaff removal versus AeroSweep Chaff, AeroSweep Chaff versus AeroSweep Fines, fewer shakes versus more shakes, fixed shake count versus visibly filled ridges, trapped fines discarded versus mostly reintroduced, or dedicated sieve versus AeroSweep Fines.

    What AeroSweep does not control

    AeroSweep controls one preparation step. It does not control roast level, grinder burr geometry, grind setting, particle-size distribution before separation, water chemistry, brew time, press behavior, bypass, filter behavior, or sensory interpretation.

    Existing Solutions and Their Limits

    4.1Catch-cup blowing

    Catch-cup blowing is simple, fast, and requires no extra tool. It works well enough that many brewers continue to use it. Its limitation is geometry: a small exposed surface area and high technique dependence.

    AeroSweep Chaff does not change the basic separation idea. It changes the working surface. The grounds are moved from a narrow catch cup onto a wider tray where airflow and gentle shaking have more exposed area to work with.

    4.2Dedicated fines sieves

    Dedicated sieves such as Fellow Shimmy and KRUVE are the more precise existing solution for fines removal [8][9]. They solve a real problem, but they also add another transfer, another tool, another shaking step, and more workflow cost.

    AeroSweep Fines does not belong to that category. It does not separate by exact micron size or provide a defined particle band. Its value is different: it traps some fines during the same airflow and shaking step used for chaff removal.

    4.3Paper and tissue methods

    Improvised paper methods show that brewers have looked for low-friction ways to remove fines without a dedicated sieve [10]. But paper methods are difficult to control and can introduce their own workflow problems. Brew Supply prototype testing found this direction weak inside the AeroSweep workflow, with paper or tissue approaches trapping only around 0.1 g or less.

    That does not prove every paper method is ineffective. It supports a narrower design decision: if fines trapping is part of AeroSweep, the trapping mechanism should come from the printed floor geometry rather than from added paper.

    Evidence, Prototype Testing, and Community Validation

    7.1Current prototype observations

    Prototype testing of AeroSweep Fines suggests that the fines-trapping floor can retain a meaningful amount of fines during normal use. In tests using 20 g of ground coffee, approximately 1 to 3 g of fines were typically retained by the tool depending on the amount of shaking.

    This was measured practically by inferring how much coffee did not transfer into the AeroPress chamber afterward, with the retained material visually confirmed as fines. The observation matters because it shows the floor is not merely cosmetic. It changes what enters the brewer.

    7.2What remains unmeasured

    The current evidence is still limited. AeroSweep Fines has not yet been tested across a broad set of coffees, grinders, roast levels, grind settings, humidity conditions, and users. It has not yet been measured against exact particle-size thresholds or compared systematically against dedicated sieves.

    The same is true for AeroSweep Chaff. The design rationale is clear, but the exact improvement over catch-cup blowing has not yet been quantified. Useful next questions include how much chaff remains after each method, how long the workflow takes, how much coffee is lost during transfer, and how repeatable fines retention is at a fixed shake count.

    7.3A practical community testing protocol

    A basic community test should capture coffee dose before AeroSweep, coffee and roast level, grinder and setting, AeroSweep version, number of shakes, airflow method, whether ridges were visibly filled, coffee transferred into the AeroPress, coffee retained in AeroSweep, fines recovered after knocking, and sensory notes.

    The protocol should remain simple enough for real use. A competitor preparing for a routine does not need a lab setup. A scale, a repeated shake count, and a short record of retained and transferred coffee would already provide useful data.

    Use Cases, Limitations, and Practical Scope

    8.1Primary users and best-fit use cases

    AeroSweep is mainly designed for brewers who care about preparation repeatability: competition AeroPress brewers, brewers preparing for AeroPress competitions, coaches helping competitors compare routines, advanced home brewers running structured experiments, and Brew Supply contributors testing particle-preparation workflows.

    AeroSweep Chaff is best when the brewer wants a wider, more repeatable surface for chaff removal but does not want intentional fines trapping. AeroSweep Fines is best when the brewer wants chaff removal plus partial fines trapping during the same step.

    8.2Limits of both versions, plus cleaning and maintenance

    AeroSweep controls one preparation step. It does not guarantee better coffee, more clarity, less bitterness, removal of all chaff, removal of all fines, perfect fines recovery, or exact micron-level separation. It does not replace a dedicated sieve or sensory dial-in.

    AeroSweep Chaff makes chaff removal less cramped, not perfect. AeroSweep Fines makes fines trapping practical, not precise. AeroSweep Fines also requires more attention to cleaning because fines collect in the ridges. After use, the floor should be brushed out with a firm brush, rinsed if needed, and dried fully before storage.

    8.3Food-contact and material considerations

    AeroSweep is used with ground coffee before brewing, so material and cleaning choices matter. Sensible precautions for FDM food-contact tools include using suitable materials such as PETG, preferring food-contact-labeled filament where available, using a clean nozzle dedicated to appropriate materials, and preferring stainless-steel or titanium nozzles over standard brass nozzles [11][12].

    These considerations apply to 3D-printed coffee tools broadly. They are not unique to AeroSweep. With appropriate material choice, clean printing practice, and normal cleaning, AeroSweep fits a realistic competition-prep use case.

    Conclusion

    AeroSweep addresses a narrow but real workflow problem in competition AeroPress brewing. Chaff and fines removal already appear in high-level recipes. The unresolved issue is that the physical workflow is often improvised: narrow catch cups for chaff removal, separate sieves for fines, and extra transfers that add time and risk.

    AeroSweep Chaff changes where chaff removal happens. It moves the grounds from a narrow catch cup into a wider tray, giving airflow and gentle shaking a more suitable surface to work with. AeroSweep Fines changes what that same step can do by adding a printed fines-trapping floor for partial fines trapping and removal during the chaff-removal workflow.

    The tool does not decide whether chaff or fines should be removed. It does not guarantee a better cup. It does not replace a dedicated sieve. Its contribution is narrower and more practical: chaff is the visible problem, separation geometry is the real variable, and AeroSweep makes that separation step wider, faster, and easier to repeat.

    References

    Related links

    Related guides and tools

    Use the whitepaper for the workflow and limitations, then follow the related pages for adjacent prep-state control, matched-dose work, and measurable press refinement.

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    AeroPress precision tools guide

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    Read AeroPress precision tools guide
    AeroPress competition gear checklist

    Practical gear planning for competition prep, workflow control, and repeatable service.

    Read AeroPress competition gear checklist
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