All the sheet steel parts may be tacked on the frame but the door, which is
secured by hinges.
The frames of the six trays are made of 3/4" wood 10-1/2" wide and 20-1/2" long. Make the bottom of the trays of wire cloth (20-1/2" × 10-1/2"). This is tacked on the underside of the frame of the trays.
By referring to the drawing it will be observed that the bottom
tray is shoved back as far as it will go; the next tray above is
pulled as far front as the door will admit; the next tray is shoved
back and so on with each tray shoving one to the back and pulling
the other to the front. The object of this arrangement is to allow
the heat to pass over and around the ends which causes a more
rapid movement of the air current. This is more important in
drying than the heat.
It may be necessary to shift the trays by putting the top one on the bottom and the bottom one on the top during the drying process so as to dry the products more uniformly.