Silicone Mold Guide
How to make and cast silicone molds with a 3D printer — two-piece mold design, sprues and vents, choosing silicone, print settings and troubleshooting.
How to Make a Silicone Mold with a 3D Printer (Complete Walkthrough)From a 3D model to a finished cast — print the mold shell, pour silicone, demold. A step-by-step guide with the supplies you need.Two-Piece Mold Design — Parting Plane, Seal Ridge, Locator Pins, UndercutsThe elements that make a two-piece mold seal, align and release the cast, explained one by one so you can pick the right parameters.Sprues and Air Vents — Side Pour vs Top Pour, Filling Without BubblesWhere the sprue and vents go, how big they should be, and pouring technique that keeps bubbles out of a closed two-piece mold.Choosing Casting Silicone — Tin vs Platinum Cure, Shore Hardness, Cure InhibitionThe difference between tin-cure and platinum-cure silicone, how to pick a Shore A hardness, food and skin safety, and why platinum silicone sometimes refuses to cure.3D Printing the Mold Shell — Material, Layers, Orientation, Post-ProcessingPLA vs PETG, printing without supports, layer settings for a smooth cavity, dimensional tuning for the locator pins, and release agents.Silicone Mold Troubleshooting — Won't Cure, Leaks, Bubbles, Won't ReleaseThe problems people hit most with silicone casting and 3D-printed molds, organised by symptom with causes and fixes.
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