Best-Ever Solar Food Dehydrator Plans: 12 Simple Steps To Completion

Categories: DIY

Step 1: Mark the Cutting Diagram

Most of the wood required for these solar food dehydrator plans can be cut from a single 4-by-8-foot sheet of three-quarters-inch-thick exterior-grade plywood. Measure and mark the plywood using the cutting diagram (above) as your guide. Note that the dryer sides are cut in a single piece so there’s no joint between the collector box and the drying chamber. You should mark the dehydrator’s sides on opposite edges of the plywood sheet to leave space in the center for the other pieces you’ll need.


The angle of the sides on this design is perfect for drying food at 36 degrees latitude in North Carolina. The unit will function well anywhere, though, offering maximal performance between March 21 and May 21, and from July 21 to September 21. If you prefer your food dryer to have the best possible angle for your latitude, refer to the suggestions in Table 1 (below). Here’s how to transfer a customized angle to the plywood sheet: Measure and mark 13 inches in from the corner on the edge of one long side, place a protractor on the mark, find the correct angle for your latitude on the protractor, and draw that angled line up from the mark to the adjacent short edge of the plywood sheet. The length of this line should be 30 inches. If you measure the line and discover it’s not 30 inches, move a straightedge to the right or left of the original line — and parallel to it — until you get a 30-inch-long line at the correct angle for your latitude, then mark the line again. Using the cutting diagram, measure and mark the remaining lines for both of the dehydrator sides, then fill in the empty space on the plywood sheet with lines for the vent covers and the front and back of the drying chamber. 

Table 1: Dehydrator Angles for Different Latitudes 

Latitude Degrees Angle in Degrees 
20 100
30 110
40 120
50 130
60 140

Step 2: Cut the Sides

Place the marked sheet of three-quarters-inch plywood on top of two sawhorses and cut out the pieces using a circular saw. Be sure to cut straight lines because you want the dehydrator box to be airtight. Make plunge cuts when cutting out the angles of the drying chamber and roof for the dehydrator’s sides. After cutting out the two large sides, lay one on top of the other and check to see if they’re the same size and shape. If not, mark the areas that are different and trim the larger piece with a circular saw so that both sides match. Cut the remaining components from the plywood sheet, and prime and paint the interior and exterior of all wooden pieces to reduce warping which could create an air leak. 

Step 3: Cut the Braces

Before beginning assembly, you’ll need to cut some braces to support the components of the solar dehydrator on the interior. Most of these braces will serve more than one function so it’s important to use the correct one at each location. See the detailed drawing ("How it Works," above) for proper sizing and placement of the braces.

To make the braces, cut some three-quarters-inch-thick pine boards into strips using a rip guide on a circular or table saw. You’ll need to cut the following sizes, all of them 22 1/2 inches long: six pieces measuring 3/4-inch by 3/4-inch; four pieces measuring 3/4-inch by 1 1/2 inches wide; and one piece measuring 3/4-inch by 5 1/2 inches. The 5 1/2-inch brace needs a bevel down one side so that it will line up with the angle where the drying chamber and collector box meet. You can cut this bevel with a circular saw adjusted to a 116-degree angle (your angle will be different if you’re building a dehydrator customized to your latitude) and with a rip guide installed. 

To install the braces, place the two large sides upside down and side by side on sawhorses so that they’re balanced on their edges and spaced about 2 feet apart. Install the 3/4-inch-by-5-1/2-inch beveled brace between the sides where the collector box and drying chamber meet, and set a 3/4-inch by 3/4-inch brace at the air intake end of the collector box. Be sure to pre-drill the holes using a No. 8 countersink bit, and fasten the braces in place with 1 5/8-inch No. 8 exterior-grade Phillips screws. Now the two dehydrator sides should be held together by the two braces. 

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