How to cut HDPE plastic
High-density polythene (HDPE) is a versatile FDA- and USDA-approved food-grade plastic. You could have a HDPE cutting board in your kitchen. HDPE is cut-resistant and milky white in colour.
Like most thermoplastics, the heat generated while you are cutting it will cause the plastic to melt and fuse together behind the cutting blade. Using the appropriate cutting tool and lubricating the cutting area will ensure success when cutting the HDPE plastic.
Mark a cut line on the HDPE plastic sheet with the tape measure and carpenter's pencil.
Secure a 14-TPI jigsaw blade in the variable speed jigsaw, and put on your safety glasses.
Lay the marked sheet of HDPE plastic flat on the worktable and slide the plastic sheet so the marked cut line rests 1/2-inch beyond the edge of the worktable.
Place one pair of self-locking C-grips at each location that the side of the plastic sheet intersects the edge of the worktable, to hold the plastic sheet in place while you cut the sheet to length.
Fill the spray bottle with water.
Align the jigsaw blade with the marked cut line, start the jigsaw and constantly spray water on the cutting area as you apply forward pressure on the jigsaw. Keep the speed of the jigsaw slow to avoid overheating the HDPE plastic as you cut.
Dry the surface of the HDPE plastic with a dry rag after you have completed the cut with the jigsaw.
Lightly sand the cut edge of the HDPE plastic with 120-grit sandpaper to smooth the rough edges from the cut plastic sheet and release the self-locking C-grips to free the cut plastic sheet from the worktable.