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Homemade Fan Sprayer, Coanda Effect, Teaching KNF to the World

Drake covers the Pure KNF Foundation's mission and points folks to knfsupport.com for the Q&A archive and university research papers on KNF microbes.

He then shows the fan sprayer he built from two Home Depot fans wired to spin opposite directions, so the air comes out in a straight column instead of scattering. He explains the Coanda effect, references Gerald Pollack's work on lifters, and compares his roughly $200 build to $5,000 commercial tractor mist sprayers. The plan: mount it on his truck bed with an inverter and a lazy susan.

The second half is Albert Bartlett's exponential theory homework: a bottle of doubling bacteria is only half full one minute before it's full. Drake runs a live spreadsheet showing that if he teaches two people and they each teach two more, the doubling reaches 8.5 billion people in 33 cycles, or about 462 days if each cycle takes two weeks. Teaching 10 people instead of 2 only shaves it to 29 cycles.

He also shares the disgustingly cheap microbe recipe (weeds, water, a handful of soil, two weeks, diluted 1:100) and mentions his farm Airbnb and $1,200 week-long course.

Questions answered

  • 4:44 What is Pure KNF Foundation's mission and where can I find past Q&A? — Mission is to balance life through microbial awareness, education, and action; knfsupport.com archives past office hours Q&A and university research papers.
  • 8:32 How do you spray a whole pasture without driving a tractor back and forth? — Drake built a homemade fan sprayer from two Home Depot fans so it can throw a low-pressure mist far out instead of relying on high pressure.
  • 15:57 What is the Coanda effect and why does it matter for the sprayer? — Curving the fan's intake so air hugs the surface pulls in more air and speeds the thrust, the same trick used in ducted-fan efficiency videos.
  • 20:26 Any research behind pushing mist further with fans instead of pressure? — Drake points to Gerald Pollack's work on lifters and contra-rotating fan studies showing paired fans push air in a straight, concentrated column.
  • 23:18 How does the DIY fan sprayer compare in cost to a commercial tractor mist sprayer? — Commercial tractor mist sprayers run about $5,000; Drake's two contra-rotating fans cost roughly $200.
  • 26:14 What is the exponential theory video Drake assigned as homework? — Albert Bartlett's 'The Most Important Video You'll Ever See,' which explains how doubling growth sneaks up on resource limits.
  • 28:46 Why is a bottle of doubling bacteria only half full one minute before it's full? — If bacteria double every minute and the bottle is full at noon, it must have been half full at 11:59, a minute earlier, not at 11:30.
  • 35:42 If Drake teaches two people KNF and they each teach two more, how far does it spread? — Running the doubling in a spreadsheet, that pattern reaches 8.5 billion people after 33 cycles of teaching.
  • 43:02 How long would it actually take for the whole world to learn KNF this way? — If each teaching cycle takes about 14 days, the whole world would know natural farming in roughly 462 days.
  • 45:17 Can I come learn KNF hands-on at the farm? — Yes, Drake rents rooms on Airbnb at the farm and offers a full week course for $1,200 including lodging.
  • 49:22 What's the cheapest way to start making fertilizer with almost no money? — Put weeds in a bucket with water and a handful of microbial-rich soil, let it sit two weeks, then dilute the juice 1:100 for general use.
  • 52:12 Does teaching 10 people instead of 2 speed up spreading KNF much? — Only a little, it drops the doubling from 33 cycles down to 29, about 13% faster, not a big difference.

Topics: imo, fan sprayer, coanda effect, contra-rotating fan, exponential growth, misting, pasture spraying, airbnb course, disgustingly cheap microbes, gerald pollack, knf support, pure knf foundation

KNF Office Hours is a free live Q&A every Sunday at 9 AM HST. Bring your question to pureknf.org/learn/questions or join live.

In this episode

  1. 0:00 Intro and Welcome
  2. 1:14 I Ching Reading: Possession in Great Measure
  3. 4:20 Pure KNF Mission, Support Site, Research Papers
  4. 8:22 Homemade Fan Sprayer for Pasture Spraying
  5. 15:46 Ducted Propellers and the Coanda Effect
  6. 18:32 Fan Sprayer Parts, Inverter Power, Pollack's Lifters
  7. 23:09 Commercial Tractor Sprayers vs Backpack Misters
  8. 24:57 Spraying Public Spaces with IMO
  9. 26:06 Exponential Theory and the Bacteria-in-a-Bottle Video
  10. 34:35 Teaching Two People: The Doubling Math
  11. 45:00 Learning KNF at the Farm Airbnb
  12. 47:34 Malthusian Logic and Doubling Periods
  13. 52:12 Teaching 10 People vs 2: Does It Speed Things Up?
  14. 54:36 Why Exponential Growth Beats Resource Management

Transcript

Auto-transcribed with Whisper. Click any timestamp to play from there.

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