CONSELF | How to close STL holes
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How to close STL holes

How to close STL holes

It is quite common to encounter polygonal mesh files which are affected by different types of “problems”. A typical shortcoming that appears quite often is represented by open surfaces or surfaces with holes. This issue can be caused by different factors: a 3D scanned geometry with some missing features, a corrupted original NURBS file and so on. This is why a tool able to “heal” polygonal meshes/geometries, accurately and appropriately filling these holes, is really interesting. In this post we present our “Polygonal mesh hole filler”, showing how it can solve this tricky problem in an accurate and straightforward way. And it is completely accessible through your common web browser for free!

Polygonal surface meshes with holes

Polygonal surface mesh files are very common in the field of engineering simulations. For example every STL (STereoLithography) or OBJ geometry is part of this family. And surface meshes obtained from NURBS geometries discretizations belong to the same group too.

In this post we will use as an example the file shown in the image on the right. It is a STL file of a fan. As you can see in the zoomed zones, the file has two holes on two fan blades. One hole (lower part) is in a planar region of the blade, while the other one (upper part) is in the leading edge, a curved part of the blade.

STL geometry with holes

STL holes perfectly filled

The hole fixing process

Given the input geometry, the tool does not require any additional info or setting. It automatically finds all holes present in the geometry and calculates the most appropriate triangulation to close them with high quality triangles.

The example considered here has two different type of holes from a geometric point of view. In fact, one is in the middle of a planar surface, while the other is exactly on a curved one. This particular configuration has been selected to show how well the “Polygonal mesh hole filler” tool behaves, reconstructing the missing piece of surface accordingly to the local topology.

The resulting STL file is shown in the image on the left, in red it is possible to see the two patches covering zones where holes were present. From this image, as well as from the video tutorial below, one can clearly verify how smoothly the patch is connected with the original geometry, even for the hole in the curved part.

“Using CONSELF Tools I can fix my STL files with a one-click operation inside my browser! It’s amazing how well it fills all holes I have in my meshes with best quality triangular elements.”

How to close STL holes with CONSELF: the video tutorial

The tutorial video on the right shows you how to use CONSELF Tool “Polygonal mesh hole filler” to fix your polygonal files with holes. Here are the steps shown:

  • Navigate to the Tools section through the left bar menu
  • Select “Polygonal mesh hole filler” from the Tools list
  • Choose the file in your local machine you need to fix and click on the “Submit” button

The upload will start and then the processing will be launched. Once it finishes, the filled file will be shown in the graphical window and it will be available for download.

The Tool is completely free! To use it, you have just to register here and sign up the 100% free WELCOME plan on this page.

How to close STL holes video tutorial

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CONSELF wants to make state of the art, cutting edge technology, available to every professional in the globe.

CFD & FEM simulation software is a very powerful tool, with its adoption optimization and innovation can be achieved in every field. To make this instrument accessible to everyone means lowering costs, but mainly to develop an infrastructure that favours a super-easy adoption by market new entrants.

CONSELF is highly committed and will pursue this goal working side by side with professional and industries to define the best strategies and solutions.

Alessandro Palmas –

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