Analyzing STL Files

Introduction

Analyzing STL files for "printability" (i.e. problems or defects), or the amount of plastic or filament needed is quite useful.

This page attempts to document solutions to this problem.

Printability Research

Analyzing for "printability" or checking for problems or defects seems easier or more common than analyzing for the amount of plastics needed.

This website analyzes for the following "printability":

• Model issues: This will indicate whether the model has any issues or not.
• Non-manifold edges: the number of non-manifold edges in the model (highlighted in red inside the editor).
• Boundary edges: the number of boundary edges in the model (highlighted in magenta inside the editor).
• Dimensions: the dimensions of the 3D model in centimeters as width, height and depth.
• Object information: the number of triangles, number of vertices and the volume of the model.

Here's another website I found that offers a similar service, and has a online demo:

• https://www.3dhubs.com/knowledge-base/fixing-most-common-stl-file-errors/

Checks for common STL errors:

• Boundary edges
• Intersecting faces
• Non-manifold edges
• Over-refined mesh {over-refined-mesh}

The also have an online printability analyzer:

• https://www.3dhubs.com/manufacture/

Looks like there's only paid solutions, rather than free open-source ones.

I also stumbled across a library called skeinforge (used by Rep-Rap see also) that converts STL files into G Code which could be useful.

Determining Amount of Filament Needed Research

This problem seems easier to solve than the "printability" problem.

See stl-calc on GitHub that can determine the following from a STL file with relative ease:

• Volume
• Weight
• Density
• Triangles Count

There are numerous online "3D Printing Calculator" websites that tell you similar information:

• http://tools.3deee.ch/f_calculator

With this calculator, you can convert the length of 3d printing filament into the weight of the 3d printing filament and the volume of the 3d printed model. You can also upload an STL-file* to determinate this values and you'll also see a slighlty buggy preview of the model.

• 3D Printing Price Cost Calculator Tool
• 3D Printing Mass Calculator

Academic Research Papers

• Analysis of STL files
  • Alternative link to same paper on a different website