An OBJ, ready for the slicer.
Turn an OBJ into an STL in your browser, nothing uploaded: the shape in millimetres, standing on Z as slicers expect, checked before you download it.
By Suraj Kumar4 min read
Slicers for 3D printers take STL, and many models come as OBJ. The two hold the same triangles; what changes is what is left out and which way is up. KeepSimp turns one into the other in your browser.
Drop the OBJ and download the STL.
Open OBJ to STL and drop the .obj on it. The model is shown at once, with the STL chosen under Turn it into.
Choose the unit the OBJ was made in under Its numbers are in if its size looks wrong: OBJ files do not say. The STL is written with the same numbers unless you choose another unit under Write its sizes in.
Press Download STL. Before the file is offered, KeepSimp opens it again with its own reader and counts its triangles and measures its size; a file that does not match the model is not offered, and the page says what was wrong.
What an STL cannot hold.
An STL is triangles and nothing else: no colours, no materials, no pictures and no parts. The page lists what the OBJ had that the STL leaves out before you download.
Every part becomes one shape. That is what a slicer wants; it separates pieces again if they do not touch.
Standing the right way up.
Animation programs stand OBJ models on Y; printers and CAD programs stand STL on Z. The STL is turned a quarter round so the model sits on the bed as it stood on the floor, never mirrored.
If the OBJ came from a CAD program and already stood on Z, choose Z is up under More options before converting.
Further reading
Topics: obj to stl · convert obj to stl · obj to stl converter · obj to stl for 3d printing · obj to stl free
A little less theory. A little more doing.
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