Hello all. I’m relatively new to 3D printing and our Form3+ printer. I just printed this part and it printed with a bunch of flat edges all the way around the part, rather than a completely smooth surface. Any idea why this is or is there anything I could have done differently to avoid this? It was modeled as a smooth part using Autodesk Inventor and exported as an stl file prior to importing/printing. Thanks for any help!
Sounds like your STL was low poly
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Is there a setting within Inventor to change this before exporting to an STL or possibly something within the PreForm application to help refine that? Sorry, this is all completely new to me.
I have no experience with Inventor, but I am confident there is a way to adjust this. Google “STL output settings Inventor”
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Hi @jysidro,
@dylanwalter1 is correct, this is an issue that comes from converting CAD models into STL files. When a model is saved as an STL, it gets tessellated into a mesh of triangles, which means curved surfaces are approximated by a series of flat facets. If the resolution is too low, those curves can look jagged.
One way to avoid this is to import the original STEP file directly into PreForm, which maintains the model as precise NURBS-based geometry rather than a faceted mesh. A recent PreForm update allows you to import STEP and other CAD files directly, which preserves smooth surfaces without having to rely on tessellation.
If you’ve ever worked with vector graphics (like an SVG) versus raster images (like a JPEG), it’s a similar concept. A vector file can be infinitely scaled without losing quality, whereas a raster file is made of pixels and can appear jagged if the resolution is too low. Similarly, an STL file is like a raster image, where smooth curves get approximated with polygons, while a STEP file keeps the original mathematical representation intact.
That said, if you do need to work with an STL, exporting it with a higher resolution (smaller triangle size) is the typical fix for reducing visible faceting.
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Awesome, I will give this a shot! Thank you all for the help. I’ll follow up on the results.
That did the trick! Didn’t realize there was an update allowing STEP files to import so that’s good to know. Thank you all for the help.
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