An STL, made ready for a slicer.
Repair an STL in your browser with nothing uploaded: holes and faces turned the wrong way found and shown on the model, repaired, and what is left said.
By Suraj Kumar5 min read
A slicer needs a closed shape: every edge shared by two faces, all turned outwards. An STL with holes, faces turned the wrong way or repeated triangles prints badly or not at all. KeepSimp finds what is wrong, repairs what can be repaired without guessing, and says what it left.
Drop the STL to check it.
Open Repair STL and drop the file. It is checked at once: holes and the edges around them, edges between faces turned opposite ways, edges shared by three faces or more, triangles with no area and triangles that repeat another are counted, and the edges in the way are drawn on the model in red.
A model of several separate pieces is fine to print, and the page says how many there are.
What Repair does, and does not.
Repair joins corners at one place, takes out triangles with no area or repeated, turns faces to agree with their neighbours, fills holes of up to 64 edges with a fan of triangles, and turns closed pieces right way out. Then the model is checked again.
It never guesses at a missing shape: a large hole, or edges shared by three faces or more, are left and said. Undo takes the repair back.
Download it again.
STL and 3MF are offered under the check, in millimetres, standing on Z. Every file is read back and measured before you get it.
Further reading
Topics: repair stl · fix stl file · stl repair online · non manifold stl · close holes in stl
A little less theory. A little more doing.
Try it on your own terms, with a free browser tool.
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