Slasher Spheres: Ghostface

I have always loved both the creature-catching world of Pokémon and the classic slasher vibes of the Scream franchise. There is something really fun about mashing up two completely different parts of pop culture, and seeing other themed spheres in the community inspired me to design one for my own shelf.

The result is the Ghostface Slasher Sphere. It captures the elongated look of the iconic mask—including deep, expressive eye cavities and the signature open-mouth expression—while keeping the clean, nostalgic sphere profile. The bottom hemisphere features an integrated flat footing so it sits solidly on a desk or shelf without rolling away.

FEATURES

• Multi-Part Snap Assembly: Interlocking shells, alignment core, and detail chips let single-extruder printers produce a clean multi-color display piece with zero mid-layer pauses.

• Natural Shadow Depth: Eye and nose pockets are cut deeper than the chip inserts, creating a recessed physical drop that casts natural shadows just like the movie mask.

• Anti-Roll Base: The bottom hemisphere includes a built-in flat footing, keeping the sphere stable on flat surfaces without needing a separate display stand.

• Heavy-Duty Alignment Core: A large rectangular internal alignment peg locks the top and bottom hemispheres together and prevents twisting.

• 100% Support-Free: Hemispheres and dividing rings print with their flat mating faces directly on the build plate for smooth exterior curves without support cleanup.

• Open Source: Parametric OpenSCAD source files and parameter presets available on GitHub under Cold Front Forge.

MODEL VARIANTS & FILES

Files are provided as individual single-color STL meshes ready for plate sorting:

• Top Shell (ghostface-ball-top.stl): White upper hemisphere with recessed eye and nose cavities.

• Bottom Shell (ghostface-ball-bottom.stl): Black lower hemisphere with flattened base and dedicated mouth pocket.

• Center Dividing Ring (ghostface-ball-ring.stl): Black equatorial band.

• Core Alignment Peg (ghostface-ball-filler.stl): Rectangular internal alignment block.

• Front Button Assembly (ghostface-ball-front-ring.stl & ghostface-ball-button.stl): Two-piece actuator and bezel.

• Face Detail Chips: Black eye and nose inserts (ghostface-chips-black.stl) and white mouth insert (ghostface-chips-white.stl).

RECOMMENDED PRINT SETTINGS

• Orientation: Flat on the bed, equator face down (no supports needed). Core peg printed flat on its side.

• Material: PLA or PETG.

• Layer Height: 0.20 mm.

• Wall Generator: Arachne (mandatory to resolve thin walls around facial sockets).

• Wall Loops: 3 to 4 walls for solid socket floors.

• Infill: 15% Gyroid for hemispheres; 100% solid infill for small chip inserts to prevent snapping during installation.

• Seam Position: Back / Rear (keeps seams off the face and button bezel).

• Elephant Foot Compensation: 0.15 mm (critical to keep tight chip tolerances from flaring).

• Brim: None required on clean PEI.

ASSEMBLY INSTRUCTIONS

1. Install mask inserts: Press the black eyes and nose into the top white shell. Press the white mouth insert into the pocket on the black bottom shell.

2. Build the core: Slide the rectangular filler peg into the bottom hemisphere, slide the center ring over the peg, and press the top hemisphere down until flush.

3. Install the front button: Press the red button into the black bezel ring, then press that combined assembly into the front equator opening. The bezel locks over the top cutout of the mouth.

4. Adhesive note: The friction fit holds firmly on calibrated printers, but a tiny drop of CA glue inside the chip pockets or behind the button housing guarantees permanent stability for display.

Designed by Cold Front Forge. Open-source under Creative Commons (CC BY-NC-SA 4.0).