Rendel Farms Ramp Sprayer (or

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Rendel Farms Ramp Sprayer(or How a Navy Nuclear
engineer applies the K.I.S.S. principle)

• Designed and built by Brent Rendel

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The Sprayer

• 7 tip sets on 20 center
• 4 solenoid control valves
• 50 gallon poly tank
• PTO-driven roller pump
• 1 supply line
• ½ spray line

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Spray Tips

• Hypro Fastcap 6-Jet Liquid Fertilizer tips
• 1x Tips - 0.015
• 2x Tips 0.03
• 4x Tips 0.06
• 8x Tips 0.15 (see later notes regarding this
  tip size)

4
Valve Bank

• 4 TeeJet 144A 3-way Directo Valves
• Throttle valves allow adjustment of off bypass
  flow to minimize system pressure changes as
  various valves cycle
• Pressure Regulator at bank exit proved to be
  unnecessary. System pressure controlled by
  throttle valves

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Operating Station

• Analog Control
• 12VDC system

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Control Panel

• Master Switch controls system power
• 3-position rate switches control each solenoid
  valve
• Off always off
• On always on used during calibration, cleanout,
  etc.
• Auto Valves controlled by Switch 1 and Switch
  2
• Pilot lights indicate when power is applied to
  respective circuits

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Ramp Control Operation

• Shown in Ramp Position 13 (1x, 4x, and 8x
  solenoids powered)
• Ramp is applied by
• Begin traveling at 3 MPH, Switch 1 at 0
  position, Switch 2 at 6position, Solenoid
  Switches in Auto, Master Switch On
• Rotate Switch 1 at regular intervals until
  Switch 2 position is reached
• Rotate Switch 2 at regular intervals until Off
  is reached
• Best method was simply counting to 3 between
  positions traveled about 13 feet during each step

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Simple Analog Guts

• 4-pole, 11-position rotary switch for Switch 1
• 2-pole, 11-position rotary switch for Switch 2
• Fuse protection for master power and each spray
  solenoid

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Sprayer Calibration Spreadsheet

• Developed an Excel spreadsheet to assist in
  calculating all the various parameters to lay
  down the ramp
• Also provides flow information for sprayer
  calibration
• Spreadsheet also contains list of most major
  components purchased to build sprayer
• To open file, right click on spreadsheet image
  and select Worksheet object ? Open

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Notes

• I used ½ spray line from valves to booms, but I
  could not generate sufficient flow to end tips on
  8x boom. I blanked off all end tips for corn
  ramps (5 tip sets vice 7). I am going to try
  upping the 8X hose to ¾ out of valve and teeing
  it off to two ½ lines to feed those tips. If
  this still isnt enough, I will probably convert
  boom to only 5 tip sets either keeping 20
  spacing or spreading out to 30 spacing for wider
  coverage. 20 x 5 tips provided very good
  application for 3 rows on corn.
• Switch 2 is only a 2-pole switch, so final high
  rate ramp marker could only use 2 solenoids.
  Using 8x and 4x solenoids provided a 12x rate
  which should be fine as a visual marker.
• I originally had a 5th throttle valve installed
  on the outlet of the 8x valve to compensate for
  using 0.15 tips. Due to ½ line flow
  restriction, I had to remove that valve
  completely and still barely reached 8x flow from
  those tips. I think upping the hose size will
  necessitate adding this throttle valve back.
• Its a little tricky to balance the by-pass flow
  throttle valves, but when done properly, I could
  maintain desired pressure (40 psig) consistently
  across all 15 spraying steps.

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Additional Pictures