BasicCAD› Features› STL Editor
Feature

Edit STL Files Like a CAD Model

An STL is just triangles — you can't simply type a new hole diameter into it. BasicCAD analyzes the mesh and rebuilds what it can as real sketches and features, so a downloaded model becomes a part you can actually edit.

Open an STL Free
An STL filament clip imported into BasicCAD and rebuilt as an editable Extrude feature with a 99.95% match to the original mesh, with Keep features and Convert to solid buttons
An STL clip rebuilt as an editable sketch and extrude — 99.95% match to the original mesh.

How It Works

  1. Open an STL or 3MF file (File ▸ Import, or drag it onto the window). Multi-part 3MF files from slicers come in part by part.
  2. Choose Recognize features. BasicCAD fits planes, cylinders and profiles to the mesh and rebuilds the part as sketches, extrudes, revolves, cuts, fillets and chamfers — showing a live match percentage against the original.
  3. Keep the features and edit them like any part: change a dimension, re-sketch a profile, add a hole, fillet an edge.
  4. Export a fresh STL, 3MF or STEP. Exports are tessellated from exact solids, so they come out watertight and slice without repairs.

Not every mesh can become clean features — organic sculpts and scanned objects stay a solid body. You can still cut, extend, combine and engrave that body with normal CAD features, which is often all a fix needs.

Common STL Fixes

Resize a hole

A bolt doesn't fit? Edit the recognized cut's diameter instead of guessing a scale factor for the whole model.

Add a mount or tab

Sketch on any face of the imported part and extrude a bracket, boss or screw tab onto it.

Add threads

Replace a plain hole with a modeled, printable thread from the Hole Wizard — ANSI or metric, with print clearance.

Engrave text

Add editable text or an SVG logo and cut or emboss it — even wrapped onto curved faces.

Split for printing

Cut a model that is too big for the build plate into parts, or merge several meshes into one body.

Multi-color 3MF

Paint faces and export a multi-color 3MF that Bambu Studio, OrcaSlicer and PrusaSlicer read directly.

Private by Design

Many online STL editors upload your file to a server. BasicCAD does the mesh analysis and the CAD rebuild on your own computer, in Web Workers inside the browser — the file never leaves your machine. Big files are processed in the background so the page stays responsive.

STEP and OpenSCAD Too

The same idea works for other formats: STEP files from SOLIDWORKS, Fusion or Onshape are rebuilt as editable features when possible, and OpenSCAD .scad files can be imported and converted. Designing for print from scratch? See 3D printing in BasicCAD.

Fix Your Next STL in the Browser

Import and edit for free. Export plans start at $5 a month, with a 30-day free trial.

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