# Detecting edge fillet/blend vertices on a triangular surface mesh

**URL:** https://discourse.vtk.org/t/detecting-edge-fillet-blend-vertices-on-a-triangular-surface-mesh/8278
**Category:** Support
**Created:** [April 11, 2022, 5:39pm UTC](https://discourse.vtk.org/t/detecting-edge-fillet-blend-vertices-on-a-triangular-surface-mesh/8278 "2022-04-11T17:39:42Z")
**Posts on this page:** 1
**Page:** 1

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### Author: ![drathin4](https://discourse.vtk.org/user_avatar/discourse.vtk.org/drathin4/32/4998_2.png) [@drathin4](https://discourse.vtk.org/u/drathin4)
#### Post date: [April 11, 2022, 5:39pm UTC](https://discourse.vtk.org/t/detecting-edge-fillet-blend-vertices-on-a-triangular-surface-mesh/8278/1 "2022-04-11T17:39:42Z")

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I want to detect the vertices of an edge fillet/blend of an STL file. This fillet/blend edge forms the border of the top face of a closed surface triangular mesh. I tried using the class `vtkCurvature` where I experimented with `Mean` and `Gaussian` curvature. But neither of those numerical values form any pattern of curvature. Also, I tried using `AdjustEdgeCurvature`, but that doesn’t work here. Could you kindly advise what technique could be used for detection of such an edge ? I’m pasting a snip of the mesh where the fillet edge is painted in BLUE and highlighted in BLACK. This is the principal curvature as detected in MeshLab.

 ![image](https://discourse.vtk.org/uploads/default/original/2X/c/cbf927d9e8664483a33677a1ae6b3a0e6223c1e3.jpeg)