What is the Dayton 1TDP3 blower and why use it for a winnower?

The Dayton 1TDP3 is a variable-speed centrifugal blower that provides consistent, adjustable airflow — the key requirement for a cacao winnower. Its variable speed allows calibration to the exact airflow that separates husk from nibs without carrying nibs upward. It is the standard recommendation from Dandelion Chocolate for DIY winnower builds.

What size PVC pipe should I use for a cacao winnower?

3-inch inside diameter food-safe PVC pipe is the standard specification. The column should be approximately 2 feet long. Longer columns give husk more travel distance for cleaner separation; shorter columns can work but require more precise airflow calibration. Food-safe PVC is important because the air stream contacts the nibs directly.

How do I know if my winnower is calibrated correctly?

At the correct blower speed, nibs fall through the bottom of the vertical column to the collection bin while husk is carried upward into the cyclone separator. At too-low speed, both fall through. At too-high speed, both get carried up. The right calibration produces clean separation — under 2% husk in the nib fraction by weight.

Do I need a cyclone separator on my DIY winnower?

Yes, for practical use. Without a cyclone separator on the blower intake, husk carried upward by the air stream goes directly through the blower and into your work area. A dust collection cyclone captures the husk before it enters the blower, depositing it into a collection bag or bucket for easy removal.

What is the FDA limit for husk in finished chocolate?

The FDA limit is 1.75% husk by weight in finished nibs or chocolate products. For a DIY winnower to meet this standard, calibration and possibly a second separation pass are required. Blind tasting data shows husk is indistinguishable below 2% and produces detectable defects at 5% and above.

Can I use cacao husk for anything after winnowing?

Yes. Cacao husk makes a light chocolate tea when steeped in hot water. It contains mild theobromine and has pleasant cocoa notes. Dry collected husk at low temperature before using for tea — wet husk develops mold quickly. This byproduct use makes the winnowing step essentially zero-waste.

How to Build a DIY Chocolate Winnower

The standard DIY winnower for cacao uses a 2-foot section of food-safe PVC pipe, a Dayton 1TDP3 blower, and a cyclone separator. Total materials cost is approximately $50 to $100. The result is a consistent vertical air column that separates husk from nibs at approximately 1 lb per minute — significantly faster and more consistent than a hairdryer and bowls. This guide covers the complete build.

Why Build Rather Than Buy

The alternatives at each price point have limitations. Hairdryer winnowing works but is inconsistent and limited by Dandelion’s Ten-Minute Rule — never spend more than 10 minutes hand-winnowing per batch. Commercial crackers like the Aether Deluxe start at approximately $1,800 and only become cost-effective after roughly 20,000 lbs of production.

A DIY PVC winnower fills the middle of that range: significantly better than a hairdryer, a fraction of the cost of commercial equipment. For a home maker processing 5 to 20 lbs per week, this build is the right tool.

The principle is simple: a vertical air column carries lightweight husk upward while heavier nibs fall through under gravity. The air velocity is the key variable — set too slow, and husk does not separate from nibs; set too fast, and nibs get carried up with the husk. Calibration to the right velocity for your typical nib size is the most important step.

Materials List

2-foot section of food-safe PVC pipe, 3-inch inside diameter
Dayton 1TDP3 blower (or equivalent variable-speed blower)
PVC elbow 90-degree, 3-inch diameter
PVC reducer from 3-inch to blower output diameter
Cyclone separator (dust collection cyclone, food-safe)
Food-safe collection bag or bucket for husk collection
Collection bin for nibs (bowl, bucket, or tray)
PVC primer and cement
Duct tape for initial fitting and testing
Variable speed controller if your blower does not have one

Total estimated cost: $50 to $100 depending on region and whether you source used components.

Time to build: 2 to 4 hours including assembly, initial fitting, and calibration.

The Design

The winnower works as a vertical column with three main sections:

Bottom section: The nib entry point. Cracked nibs are dropped in from the top of the vertical column. The air stream blows upward through the column. Heavier nibs fall against the air stream, through the bottom of the column, and into the collection bin below.

Middle section: The 2-foot PVC pipe, the main separation column. The length of this section determines the separation distance — longer columns give husk more time to be carried upward before exiting, which can improve separation quality.

Top section: The 90-degree elbow connects the vertical column to the blower intake. Husk carried upward by the air stream exits here. The cyclone separator is placed at the blower intake to capture husk before it enters the blower mechanism.

Assembly Steps

Step 1: Connect the blower to the top of the PVC column using the reducer and elbow. The blower draws air through the column from bottom to top. The air enters at the bottom (where you drop nibs in) and exits at the top through the blower.

Step 2: Mount the cyclone separator on the blower intake side. The cyclone uses centrifugal force to separate husk from the air stream and deposit it into the collection bag or bucket. Without the cyclone, husk goes through the blower and potentially into your work area.

Step 3: Position the column vertically. The bottom should be above the collection bin so nibs fall cleanly into it. A simple stand made from scrap wood or PVC fittings at 90 degrees works well.

Step 4: Before cementing joints permanently, do a test assembly with duct tape. This lets you adjust positioning before committing.

Step 5: Once the test assembly confirms the geometry works, use PVC primer and cement on all structural joints. Food-safe PVC cement is important — the air stream that contacts your nibs should not carry off-gassing from regular hardware store cement.

Calibration

Calibration is the most important step in building a functional winnower. The goal is to find the blower speed at which husk separates completely from nibs without carrying nibs upward.

Test material: Start with a small batch of cracked, partially winnowed material — some husk, some nibs, in the normal proportion you produce.

Test 1 (too slow): At low blower speed, both husk and nibs fall through. No separation. The air column is too weak to lift the husk against gravity.

Test 2 (too fast): At high blower speed, husk and nibs both get carried upward into the cyclone. Too much airflow.

Target: At the right speed, nibs fall through to the collection bin while husk is carried upward to the cyclone. The transition between these states is usually a relatively narrow speed range.

Nib size varies by origin. Smaller-origin nibs require less airflow than larger ones. If you work with multiple origins, note the calibration setting for each and label it.

The FDA husk limit of 1.75% by weight applies to finished products. After calibration, test your separation quality by weighing the nibs in the collection bin and comparing to the husk in the cyclone. Adjust blower speed until the nib fraction reads under 2% husk by weight.

Improving Your Build

Second column pass: Running nibs through the separator twice nearly eliminates husk below the FDA limit. First pass removes the bulk of husk; second pass at the same or slightly higher airflow clears residuals.

Adjustable feed rate: A simple feed gate (a partial block at the nib entry point that controls how fast you pour) prevents overwhelming the air column with too many pieces at once. Consistent, steady feeding produces more consistent separation.

Nib size screening: Running cracked material through a coarse screen before winnowing removes both very large and very small pieces. Large pieces (un-cracked beans) do not separate well; very fine dust from over-cracking can be carried upward with husk even at low airflow.

Husk as Byproduct

The husk you collect in the cyclone is not waste. Cacao husk makes a pleasant tea when steeped in hot water — it has light theobromine content and mild chocolate notes. Dry it at low temperature if you plan to use it for tea; damp husk develops mold quickly.

Connecting to the Full Process

Winnowing fits between cracking and pre-refining or direct melanger loading. Clean nibs from the winnower either go directly into the melanger or through a Champion juicer for pre-refining first. For the complete cracking and winnowing process, see our how to crack and winnow cacao guide. For winnowing equipment options beyond the DIY build, see our best winnower comparison.

For the complete equipment picture, see our bean-to-bar equipment guide.

Frequently Asked Questions

What is the Dayton 1TDP3 blower and why use it for a winnower?: The Dayton 1TDP3 is a variable-speed centrifugal blower that provides consistent, adjustable airflow — the key requirement for a cacao winnower. Its variable speed allows calibration to the exact airflow that separates husk from nibs without carrying nibs upward. It is the standard recommendation from Dandelion Chocolate for DIY winnower builds.
What size PVC pipe should I use for a cacao winnower?: 3-inch inside diameter food-safe PVC pipe is the standard specification. The column should be approximately 2 feet long. Longer columns give husk more travel distance for cleaner separation; shorter columns can work but require more precise airflow calibration. Food-safe PVC is important because the air stream contacts the nibs directly.
How do I know if my winnower is calibrated correctly?: At the correct blower speed, nibs fall through the bottom of the vertical column to the collection bin while husk is carried upward into the cyclone separator. At too-low speed, both fall through. At too-high speed, both get carried up. The right calibration produces clean separation — under 2% husk in the nib fraction by weight.
Do I need a cyclone separator on my DIY winnower?: Yes, for practical use. Without a cyclone separator on the blower intake, husk carried upward by the air stream goes directly through the blower and into your work area. A dust collection cyclone captures the husk before it enters the blower, depositing it into a collection bag or bucket for easy removal.
What is the FDA limit for husk in finished chocolate?: The FDA limit is 1.75% husk by weight in finished nibs or chocolate products. For a DIY winnower to meet this standard, calibration and possibly a second separation pass are required. Blind tasting data shows husk is indistinguishable below 2% and produces detectable defects at 5% and above.
Can I use cacao husk for anything after winnowing?: Yes. Cacao husk makes a light chocolate tea when steeped in hot water. It contains mild theobromine and has pleasant cocoa notes. Dry collected husk at low temperature before using for tea — wet husk develops mold quickly. This byproduct use makes the winnowing step essentially zero-waste.