Materials you will need.
1 wire hanger
1 Propane torch
1 lighter or other ignition device
1 pair of vise grip pliers
3 pieces of scrap 2 x 4 lumber
Step 1: Making the cutter
Alternatively you could create any shape with the wire hanger to fit your needs. Making a box shape would also work quite well.
Step 2: Make your cutting table, marking and aligning.
Now mark or trace your foam where it needs to be cut and place it on your cutting table. Align the styrofoam flush to the bottom edge of the fence. Next align your cutting mark on the outer edge of the fence.