How to remove lines based on a STL file?

[Geo]

See the tips in this post…

Modifying STL file to add holes. Not sure how to do it

Import the STL into SketchUp. Prior to import, look under Options button. There, set the units to Meters to avoid SU’s issues in creating tiny new geometry. [STL%20Import%20Options] The STL comes into SU as a Component. Explode the Component. Make your modifications. Make it a Component again and confirm via Entity Info that the model is a Solid Component. Solid Inspector can help you find flaws preventing it from being a Solid. https://extensions.sketchup.com/en/content/solid-inspect…