Measure the inside of your oven.
Diy plastic sheet molding.
As you ll need to put the plastic sheet into the oven this is your size limitation.
Cut 4 to 6 sheets of plasters.
Layer the sheets on top of eachother.
Each sheet should be 6 inches longer than the mold.
Create a durable mother shell.
Have a mold ready to use.
Remove the excess water by squeezing the sheets over the bowl.
Create high performance plastic parts.
Dip the sheets in bowl filled with room temperature water for 1 second.
Polycarbonate clear plastic sheet 12 x 24 x 0 0625 1 16 3 pack shatter resistant easier to cut bend mold than plexiglass.
Things you ll need 2 inch by 4 inch timber saw 3 inch wood screws drill plywood sheet 2 inch by 2 inch wood cube 2 foot by 2 foot pegboard sheet angled shop vac attachment small screws duct tape form coins shop vacuum cleaner thermoplastic sheets hobby knife stapler oven oven mitts pencil eraser.
The example here is the outside of a mold but it can work inside too.