I am using this with Home Depot's Vissani 8.8 cubic foot chest freezer, and 2 of Walmart's mainstay lasagna trays. The freezer measures 17.5" across the top and the tray measures about 16", so the supports are designed to take up about 1.4". I have left a 1" gap for air flow above each tray. The bottom tray rests at about the same height as the baskets that come with the freezer.
I expect you will want to alter the thickness of the model, feel free to adjust dimensions as needed, or create your own version with additional shelves etc.
Additionally requires about 3' of paracord, I designed it for type 3 (aka 550 lb).
Print the 2 sides of the tray supports and optionally the inside stretcher (or use a piece of wood - ½"x1"x6"), twice - one for each side of the freezer.
PETG is recommended due to the cold temperature, no supports are necessary.
Glue or screw the stretcher in place.
The paracord and the tray work together to push the tops of the supports out, keeping them from falling. If it's too slack, the supports will not support anything. If it's too tight, the tray will not sit flush when inside the freezer. Adjust your knot location until it's “just right” - the supports will slightly lean out when not under tension - see the angle in the attached picture. The other support is upright.
The author marked this model as their own original creation.