Begin with a model or dimensions
Use an STL you already have, choose a practical preset such as a soap bar or candle form, or define a cylinder or box directly when no source model is needed.
STL or simple shape to two-part mould
Turn an STL or simple shape into a printable two-part mould
The Printforge Mould Maker builds two printable mould halves around an existing model or a measured primitive. You control the casting material, parting plane, wall, clearance, registration keys, pour spout and air vents while a live exploded view shows how the halves separate. The authoritative result downloads as two STL files in one archive.
Open Mould maker in Printforge
14-day Pro trial · no credit card required
Output:Two STL mould halves
Built for production decisions
What the Mould maker handles
Control the casting interface
Move the parting plane, choose its axis and adjust clearance for silicone, resin or plaster. Registration keys keep the printed halves aligned during assembly.
Add the flow features
Set the pour-spout diameter and vent count and size, then inspect the exploded preview in the direction the real mould will open.
From source to printable model
- 1
Choose the master
Upload a printable STL or start from editable dimensions for a plain cylinder, taper or rectangular form.
- 2
Plan separation and flow
Select the casting material, parting plane, clearance, walls, keys, spout and vents around the actual master.
- 3
Inspect both halves
Use the exploded preview to check opening direction and features, then generate and test the two downloaded STL parts.
Useful for
- Soap, candle and plaster casting forms
- Prototype silicone mould shells
- Small-batch craft products built from a reusable master
- Teaching parting lines, registration and casting workflow
Plan the physical result
A two-part mould is not suitable for every master. Undercuts can trap a rigid casting or prevent the halves from opening cleanly, and a poor parting line can cut across critical detail. Inspect the separation direction and modify the master or process when simple two-part demoulding is not realistic.
Clearance, vents and spout dimensions depend on the casting material and scale. Print a small test, check for leakage and trapped air, and verify that both mould and casting materials are appropriate for the temperatures, chemicals and end use involved.
Frequently asked questions
Do I need an STL to start?
No. You can upload an STL, choose one of the simple product presets or enter dimensions for a primitive shape and adjust them before generating the mould.
What is included in the download?
The finished archive contains two STL files, one for each mould half, including the selected registration, pour and vent geometry.
Will it solve undercuts automatically?
No two-part workflow can make every undercut demouldable. Use the exploded preview to assess the opening direction and redesign the master or casting process where necessary.
One connected toolkit
Explore related 3D tools
Stamp & Embosser Maker
Turn artwork into a printable ink stamp, clay stamp or two-plate card embosser with live geometry, practical fit controls and STL output.
Learn moreClicker Button Maker
Turn artwork into a pressable, multicolour 3D printed clicker with a live preview, editable palette and colour-assigned 3MF output.
Learn moreShopify 3D Product Configurator
Let Shopify customers personalise 3D printed products, preview choices, add the configured item to cart and connect payment to production output.
Learn moreBuild the first mould maker
Start with the 14-day Pro trial, inspect the generated model and move a tested file into your normal slicing workflow.
Start free trial