Austin Reitz
All projects

Cast-iron skillet injection mold

A two-part mold for a miniature cast-iron skillet, built with SolidWorks' mold tools: I modeled the skillet, set the parting line, split the tooling, and refined the core over three revisions.

Role
Designer
Context
Makerspace TA project, summer 2026
Software
SolidWorks mold tools
Mold size
3 × 4 in
Molding material
Pour-and-cure resin
CAD model of the mold core with a skillet-shaped impression
Core half of the mold (v5), with the skillet impression and alignment holes.

The part

I modeled a small cast-iron skillet, then set it into a mold block for the second version.

CAD model of the first skillet design
First skillet model.
Skillet outline set inside a rectangular mold block
Model v3: the skillet set in the mold block.

Mold design

With the part finished, I used SolidWorks' mold tools in sequence:

  • Parting line: chose where the two mold halves meet around the skillet
  • Tooling split: cut a mold block into a core and a cavity along that line
  • Core revisions: refined the core from v3 to v5
Skillet body split at the parting line
Skillet body from the parting line step.
Mold block split into core and cavity
Tooling split into two halves.
CAD model of the mold cavity half
Cavity half (v3).

Making it

The plan was to 3D print the mold halves first, then machine a final set. Time ran short, so we stuck with 3D-printed molds and filled them with a commercial pour-and-cure resin, which kept the prototyping fast.

The first parts came out rough. The reliefs were too small, so air got trapped in the mold and kept the resin from filling the cavity completely.

What I learned

Design the part itself with draft angles from the start. Our skillet model didn't account for them well, and that limited what we could do when we designed our first molds. Venting matters just as much: air that can't escape leaves voids in the part.