Home >> Hobbies >> Other Hobbies

How to Make a Die for a Plastic Extrusion Profile

Extrusion dies are custom-formed channels at the ends of plastic extrusion machines which give plastic extrusions their shapes or profiles. The simplest die is a plate with a hole drilled in it. More complex dies may include internal manifolds, or they might morph from intake opening shapes to final shapes inside the die. Complex dies must be made with a more sophisticated milling machine than a drill, such as a CNC lathe.

Things You'll Need

CNC mill
Die plate specifications

Instructions

- 1
  Mill a die plate that fits your extrusion machine. It must fit the die opening of the machine. You also may be able to purchase a die plate -- the solid die, prior to having the die shape milled into it.
- 2
  Design the exit profile in two dimensions using computer-aided drafting (CAD) software or any graphics you can convey to a CAD draftsperson. The shape should be the cross section of the plastic extrusion you're making, with attention paid to shrinking.
- 3
  Design the entry profile in two dimensions. In the simplest die, this will be identical to the exit profile. The interior of the die is identical to the extrusion itself. Otherwise, the die opening where it collects molten polyethylene plastic will be a shape of a more general variety, like a circle, and the exit profile will be more complex.
- 4
  Design the extrusion channel in three dimensions. The extrusion channel is the way in which the opening connects to the exit of the extrusion. Again, the simplest use identical profiles all the way through the die, but more complex ones change form from entry to exit.
- 5
  Mill the die plate with a CNC mill, using the CAD design as your input. Some dies can be milled from a single piece of metal. More complex dies may require the mill plate to be cut in two or more pieces, then milled from the inside. Multi-piece dies will then have to be drilled, tapped and refastened with machine screws after the milling process.

Other Hobbies