Solar Dehydrator
Manufacturing Instructions
Materials and Tools
Qty. Materials
Qty. Tools and Fasteners
2
4’ x 8’ sheet of ¾” thick pressure treated exterior plywood
1
Power drill
1
4’ x 8’ sheet of ¼” thick pressure treated exterior plywood
1
Staple gun
1
2” x 4” x 8’ pressure treated lumber
1
Circular saw
5
1” x 2” x 8’ lumber
3
1” x 6” x 8’ lumber
1
Jigsaw or band saw
7
¾” x 1 ½” x 8’ lumber for drying trays
1
Caulk and caulk gun
30
¾” wood screws
½” x 4’ x 8’ rigid foam board insulation (R-3.0)
16
½” diameter bolt 3” long with nuts & washers
60” x 38” Corrugated steel
~50 1 ½” construction screw s
Metal lath to cover an area of 60” x 39”
1 - 2 Brass latch and hook clamp set
40 square feet of food safe drying screen (we used polypropylene mesh)
2-3
1
3-4
1
¼” to ½” Plexiglas or polycarbonate plastic cover of at least 42” x 60”
1
1
8”
diameter steel rod 3’ long
2-3
4” diameter aluminum chimney piping at least 12” long
2-3
Aluminum chimney cap to keep out rain
40
Water bottles to be filled (doesn’t need to be drinking water)
1
Exterior flat matte black acrylic paint & spray paint
2
Door hinge
Marking 4’ x 8’ Wood for Dehydrator Sides
1.
2.
3.
Take out first 4’ x
8’ sheet of ¾”
pressure-treated
exterior plywood
Mark Each of the
red measurements
along the vertical
and horizontal
edges of the wood
board
Use a straight
edge to mark dots
at each of the
green coordinates
Creating Guidelines for Cutting the Sides
1. Connect the
dots to
make guide
lines for
cutting the
wood
2. Rotate the
board 180°
and repeat
the process
Finished Product
Cutting Supports for Walls
1. Cut three 6” x 1”
boards to a length of
39”
Quantity: 3
2. Cut one 2” x 1” to a
length of 39”
• Save remainder for
drying racks
Fastening Supports into Walls
1. Use 2” wood
screws to install
the 4 supports
2. Drill lead holes
through collector
box sides prior to
screwing in
supports
3. 4 screws per
support should
suffice
Adding Support for Metal Lath
1. Start with an 8’ long 2. Cut it in half to form
1” x 2” wood board
two 48” boards
3. Use 1.5” screws to 4. Leave at least ¼”
attach each board to
clearance above
the collector box on
bottom support to
a diagonal incline
later install corrugated
steel
¼” clearance
Quantity: 2
Attaching Support Racks for Drying Trays
1.
2.
3.
4.
5.
Cut ten 1” x 2” wood boards to
a length of 26 ½” each
Install first rack by lining up
front end to support beam and
the other end 5 ½” above the
end of collector box
Space each rack 3” above the
previous one, measured from
bottom to bottom
Leave a ¾” gap from front and
back walls of drying chamber
for insulation
Use 1 ½” screws to fasten racks
• 3 screws from the outside of the
dehydrator fasten to the racks
6.
7.
A sixth tray fits on top if desired
Additional Pictures on next slide
Quantity: 10
¾”
Bottom of first
rack horizontal to
top of support
¾”
3”
5 ½”
Cutting the Bottom Board of the Dehydrator
• Cut a ½” thick sheet
of exterior plywood
to the dimensions
of 87” x 40.5”
• Use a circular saw
to cut one end of
the board inward at
an angle of 27.5°
• This will allow door
to shut flush against
this end
87.0”
0.5”
27.5°
Attaching the Bottom of the Dehydrator
1. Flip frame upsidedown and fasten
the bottom board
using 1 ½” wood
screws or nails
until secured
2. Make sure angled
cut of bottom
lines up with the
drying chamber
3. The structural
frame of your
dehydrator is now
assembled
Sizing the Wood for Drying Chamber Components
1. Take out second
4’ x 8’ sheet of
¾” pressuretreated exterior
plywood
2. You should be
able to fit all 3
drying chamber
walls (A B &C), 1
door, and 1 roof.
3. Save remainder
for water tray
(slide 41)
21”
14 ½”
15 ½”
23 ¾”
8”
Door
A
B
C
Roof
Top
Cutting the Sides of Drying Chamber
1. ¾” thick pressure treated plywood
2. 40 ½” length for each board
3. Use circle saws to cut angles
Cross-Sectional View of Each Drying Chamber Wall
14 ½”
A
51.5°
38.5°
40 ½”
15 ½”
A
A
B
B
51.5°
B
C
23 ¾”
C
C
38.5°
27.5°
Cutting the Top of Drying Chamber
1. ¾” thick pressure
treated plywood
• (Cut 40 ½” by 8”)
2. Cut three 4” holes to
insert chimneys
• Our design used two
chimneys, but we
recommend three for
increased and more
even airflow
3. Cut three screens
and staple each one
over a hole to keep
out bugs and other
pests
Cutting the Door
1. ¾” exterior plywood
2. Cut to the following
dimension:
• 21” x 40 ½”
3. Consider cutting the top
of the door to a 38.5°
angle for fastening
• (See Slide 22)
Installing Insulation
1. Installation of insulation is easiest at this point,
before fastening all of the pieces of the drying
chamber to the frame
• We made the mistake of waiting until the end to add
installation, making the process very crowded
2. Use ½” rigid foam board insulation
• We chose Owen’s Corning R-3.0 foam board
3. Staple gun can be used if thin insulation is
chosen, otherwise use a foam board adhesive
to fasten to wood
Insulating the Frame
1. Start out by cutting the
insulation to cover as
much of the inside of
the frame as possible
• All along the bottom of
the collector box
• As much of the walls as
possible
• In between drying racks
for perfection
2. A few spots to avoid
insulation are marked
in red
• These areas will be
insulated once drying
chamber components are
attached
• All red spots areas are ¾”
thick
Insulating the Drying Chamber Walls
1.
2.
Easiest to do before attaching
walls to frame
Cut and attach foam board
insulation to each of the 5 drying
chamber components
• (Walls A B & C, Door, and Roof Top)
3.
4.
Leave ¾” gap along edge of each
component to allow for easy
installation
Make sure you are attaching
insulation to the inside only of
each component
¾”
Attaching the Sides of the Drying Chamber
1. Attach each side in
the following order:
• C, B, A, Top
2. Use 1 ½” screws to
fasten each side to
the frame
Attaching the Door
1. Screw in two hinges to attach
the bottom of the door to the
bottom of the dehydrator
2. Apply rubber weather stripping
to the edge of the door frame
to create a pressure seal
weather stripping
Clamping the Door Closed
1. 2 simple brass latches
were used to create
closing mechanism
2. Screw the hook on the
front of the roof, locking it
into place
3. Screw one latch on the
front of the door and one
on the top of the door
4. Ensure spacing is enough
to create a pressure seal
when closing the door
5. Improved and simplified
process is explained on
the following slide
Room for Improvement
1. If the top of the door is
cut 38.5°, one latch may
be used
2. This will allow you to
only need to attach the
latch onto the top of the
door at the 38.5° incline
created
3. Will improve seal and
ease of operation
38.5°
Paint , Paint, and More Paint
1. Use exterior flat/matte black
paint
2. Cover the entirety of the
outside of dehydrator with a
solid layer(s) of paint
• Focus on all areas that will be
exposed to sunlight
• Painting the inside of the
collector Box is a good idea as
well
3. Paint the entire top side of
the corrugated steel, if it is
not already flat black
4. Use spray paint to cover the
metal lath
Installing Corrugated Steel
1. Cut corrugated steel to 60” x
38” and paint flat black
2. Lay steel on top of base of the
collector box
• Square front end to the air intake
3. Fasten with two screws on the
front end and two on the back
Installing Metal Lath
1. Cut metal lath to size
• Ideally it will be able to span the 39”
width of the collector box
2. Spray paint the lath flat black
3. Lay the lath on top of the
diagonal supports seen in slide 7
• 3 to 4 layers of lath is optimal
4. Screw the lath onto the support
at six locations to fasten
5. Screw the back end of the lath to
the drying chamber wall to
prevent drooping
Building Drying Trays
1.
2.
3.
4.
5.
6.
Use 1 ½” x ¾” wood planks
Cut 10 planks to a length of 26”
Cut 10 planks to a length of 36 ½”
Measure out 1 ½” from each end of every plank
• Saw this section in half
Fit two of the long planks to two of the short planks
Fasten using a ¾” wood screw in each corner
Attach Food Safe Drying Screens
1. Cut the screen to at
least the outer
dimensions of the
drying racks
2. Pull the screen tight
and staple each side
into the drying tray
3. Insert trays into
dehydrator with the
screens on the bottom
Assembling the Wheel Attachment
1. Cut two 1 ½” x 5 ½” boards to a
length of 6”
2. Cut one 1 ½” x 5 ½” board to a
length of 43 ½”
3. Screw the long board on the
end of the two shorter boards
4. Use two bolts in opposite
corners to fasten each wheel to
the outsides of the longer
board
• Use washers on both ends of bolt
• Tighten nut on opposite end
against a lock washer
Attaching the Support Legs
1. Cut an eight foot 1 ½” x 3 ½”
board in half to form two 48” legs
2. Use at least two ½” or larger
bolts on each leg as well as on
each side of the wheel
attachment
3. Make sure the legs and wheel
attachment are parallel to the
door so the dehydrator will stand
up straight
4. See next slide for positioning
Positioning
1. Leave ¼” clearance
between wheel
support board and
bottom of
dehydrator
2. Lift front end of
dehydrator 2 5 8” of
the ground when
attaching legs
¼” gap
Adding Trusses to Improve Stability
1.
2.
Cut two 1” x 2” wood boards to
a length of 32”
Cut two pieces of leftover 1 ½”
x 5 ½” board to a length of
about 6”
• These will allow the trusses to be
screwed in flush against the legs
• Bolt the each piece to the front
bottom corners of the drying
chamber (see previous slide)
• Screw the 1” x 3” boards to each
leg and added piece as seen in the
pictures
3.
4.
Cut two 6” x 1” boards to a
length of 42”
Place the two boards evenly
spaced in between the two legs
and use 3” screws to fasten
Adding Chimney Stacks
1.
2.
Cut three (or two) 4”
aluminum chimney pipes,
each to a length of at least
12”
Add adjustable ventilation
(damper) as described in
the next 4 slides
• Instructions are given for
two chimneys
• Must be modified to account
for third chimney
3.
4.
Once damper is installed,
fit the 4” chimney cap on
top to keep rain out
Carefully slide the three
(or two) chimneys into the
cutouts on top of the
dehydrator
1
2
1’
3 ¾”
1’
1/8”
Cut 4 circles of 3 ¾” diameter from board
Material: One 1’ by 1’ thin board of 1/8” or thinner
3
4
1/8”
2”
1/16”
1/8”
Drill 2 1/8” holes along center line of circles
Spaced 2” apart with their midpoint in the center of circles
File an 1/8” wide groove 1/16” deep through center
line in circles between the two holes
5
Material: Steel Rod 1/8” thick and 2’ 10” long
7
6
Bend Rod 2” from end to right angle.
4” from first bend, bend rod again to right angle.
2” from second bend, bend rod to right angle to finish handle.
8
1”
Drill holes through center lines of chimney caps 1” down
from exhaust lip with #30 drill bit or 0.1285” bit
Thread rod through chimney cap holes such that rod is
protruding 1 inch out of first chimney and that there is
A gap of 9 ¾” between chimney caps
9
Materials: 8 bolts with length of half inch and thread
diameter of 1/8 or less corresponding 16 washers,
8 lock rings and 8 nuts
10
With the steel rod in chimney caps to specified dimension in step 8, two circle made in step 4 to rod using bolts
with washers, lock rings, and nuts. When securing ensure that the flat part of circles are in parallel with the handle
Bent into the rod
11
Insert chimney caps into chimney stacks
12
Insert chimney stacks into drying chamber chimney holes
Adding Plexiglas Cover
1. Use ¼” to ½” Plexiglas
and cut to the
following dimensions
• 40 ½” x 59 ¼”
2. Lay Plexiglas flat across
the top of the
collection box
3. Staple the Plexiglas
along all four edges of
the collector box until
it is fastened as air
tight as possible
• If cover is too thick for
staples, use ¾” screws or
nails
Add Screen to Air Intake to Prevent Pests
1. Cut a screen to the
following dimensions
• 11” x 42”
2. Pull the screen tight
across the collection
box opening
3. Wrap sides of the
screen over each edge
of the opening
4. Use a staple gun to
securely fasten
Add Caulk to Improve Seal
1. Using a caulk gun,
trace any edges
where two boards
were fastened
together
2. Look specifically for
any visible air gaps
that lead to the
inside of the
dehydrator
3. Smear the caulk in
between the gaps
to create a seal
4. Repeat this process
along the edges of
the Plexiglas cover
Create a Water Tray for Thermal Capacity
1. Use ¾” thick wood for
back and bottom of
tray
• Use ½” thickness for sides
2. Cut the bottom board
to 33.5” x 24”
3. Cut back to 34.5” x 4”
4. Cut sides to 24” x 4”
5. Using 1 ¼” screws
fasten the two sides to
the side of the bottom
6. Then screw the back to
the bottom and sides
Inserting Tray and Adding Water Bottles
1. Slide tray into the
bottom of the drying
chamber
• The tray will stop and rest
on the end of the
corrugated steel
2. Mark any part of the
tray that raises above
the top of the first
drying rack
• Trim the corners of the tray
to prevent interference
3. Place 3 rows of 13 water
bottles aligned vertically
• 49 total water bottles
totaling over 40 lbs.
Time to Dry
1.
2.
Fill each tray with one layer of your
desired fruit or other food
Slice fruit thinly to speed up and
optimize drying
•
3.
4.
5.
6.
1
8”
to 3
16”
thick for bananas
Try to avoid overlapping foods as it
may compromise the drying process
For wetter foods such as tomatoes,
use paper towel or cloth to absorb
some of the juices before drying
Insert trays and close door
Wait 8 hours before checking on the
fruit or foods
• Total drying time may vary between 1 to
2 days of sunlight depending upon type
of food as well as cloud cover
7.
8.
Scrape the food screens clean after
each drying cycle
Enjoy your dried foods!