The tools
- 10 formats become STL, with a 3D preview before you download.
- Parts to measure as STL and STEP, from your own dimensions.
- No sign-up, no watermark — the file is discarded afterwards.
From object to mould, in seconds.
Upload the 3D model and download a mould ready to print: a two-part rigid mould (with a core for pots), a kit for a silicone mould, or the master for an ice and chocolate tray — always with the maths on how much material to buy. No sign-up, no credits.
How it works
Three steps, no sign-up.
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01
Upload the object
STL, OBJ, PLY — and 3MF, STEP and the rest go through our converter on their own. Small holes in the mesh are repaired on the way in.
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02
Turn the pouring side up
Rotate until the side the material goes in through faces up. The parting plane is picked for you, where the least surface locks — whatever still catches shows in red.
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03
Check the material and download
The page tells you how many ml the cavity holds and how many grams of wax, plaster or resin to buy. Both halves come out ready to print without supports.
FAQ
What people usually ask.
What is the rigid mould for?
Candles, soap, plaster, cement and resin — anything that sets and comes out of a mould that opens in two. Use a release agent (petroleum jelly, silicone spray) first: printed plastic has layer lines and the cast grips. For chocolate, ice or anything edible, printed plastic will not do: use it to make a food-grade silicone mould instead.
How do I make a mould for a pot?
Pick 'Cement pot' (or turn on 'Hollow piece'). Besides the two halves you get a core that forms the hollow: it is the outer shape shrunk by the wall you ask for, always tapering down so it pulls out once cured. It works with a solid or an already hollow STL. The top of the mould stays open: pour cement or plaster about two thirds up, push the core in until the cross seats on the block, and top up. Put release agent on the core — it is the part that grips most. The drain-hole pin also props the core on the floor.
When should I use a silicone mould instead of the rigid one?
When the piece has undercuts (a lot of red in the rigid mould), fine detail, or you want many resin copies. The kit is a shell hugging the object plus a base: silicone is poured over and, once cured, becomes the flexible mould — cut a zig-zag down the side to release the piece. The shell follows the outline on purpose: silicone is the expensive item, and the page shows how much you save compared with a box.
Is the ice and chocolate tray food safe?
The printed part never touches food: it is the MASTER. You pour food-grade platinum silicone into it, and the silicone tray is what takes the chocolate or water. Printed plastic has pores between layers and is not food safe.
What is the red area?
It is the part of the piece that locks when the mould opens in that direction (an undercut). A little red with a soft material like wax or soap still comes out; a lot of red, or a hard material like plaster, calls for rotating the piece or changing the parting axis.
What are the small holes besides the pouring hole?
They are vents: 2 mm channels at the high points of the cavity, on the parting line. Without them air gets trapped at the peak and the cast comes out with a bubble right on the ear, the horn, the tip.
How should I print the mould?
As the file comes: parting face up, no supports. 3 or more walls and 15% infill are enough — the block is solid in the file on purpose; the slicer's infill is what saves plastic. PETG takes more heat than PLA (70 °C wax softens PLA over time).
How long is my file kept?
Up to 24 hours, only so you can adjust and download again; then it is deleted. We do not use your model for anything else.
Tools
The rest of what is here.
Conversion
live
STL converter
OBJ, FBX, 3MF, PLY, DAE, GLB, STEP, IGES, DWG and DXF become STL, with a 3D preview before you download.
FreeOpen →
Parts
live
Parts to measure
Enter the dimensions and download the finished part in STL and STEP — box, bracket, adapter, spacer.
FreeOpen →
Mesh
live
Split STL
Part bigger than the build plate? Split it into parts that fit, with a colour preview first.
FreeOpen →
Mesh
live
Repair mesh
Closes holes and fixes flipped normals that make the slicer reject the file — with a before-and-after report.
FreeOpen →
Mesh
live
Resize STL
Scale by final dimension, percentage or unit change (inch to mm), without the file leaving your computer.
FreeOpen →
Mesh
live
Split 3MF by colour
A 3MF painted in Bambu Studio or OrcaSlicer becomes one solid part per colour — print each in its colour and fit them together.
FreeOpen →
Personalised
live
Lithophane
A photo becomes a relief to print and hold against the light: flat or curved, with a frame. The photo never leaves your computer.
FreeOpen →
Printing
planned
Weight and time
Estimate filament and print hours before sending the part to the queue.
Coming soon
A mould is a big, chunky print.
That is hours of printing and hundreds of grams. NEO 3D Print prints both halves and ships them — the price comes straight from the file.
Disclosure: we have a commercial partnership with NEO 3D Print and are paid for referrals. That is what pays the server and keeps the tools free, with no sign-up and no third-party ads. We recommend them because they are who we use — and the text above describes their service, not an independent review.