topic Unable to create surface patch in Inventor Forum

Unable to create surface patch

eikTSYFE — Thu, 11 May 2023 15:25:23 GMT

Dear Community,

I have a closed loop line geometry consisting of four 3D Sketches (3 splines, 1 linear) which I can not patch into a surface. There is a comparable setup (the opposite lid of the geometry), which Inventor (2024) is able to patch. This one is less skewed... (see my screenshot)
As a workaround I splitted the splines manually in order to have 2 sections resulting in 2 patches, which I can stitch together. But it would cause lot of effort on the upstream part of the process, where the lines are actually generated. Any recommendation is highly appreciated...

Re: Unable to create surface patch

Gabriel_Watson — Thu, 11 May 2023 15:55:23 GMT

Sometimes I simply remove Automatic Edge Chain (un-check that option in your BP prompt) and try it. This might take longer but at times it will produce the right result.

Re: Unable to create surface patch

eikTSYFE — Thu, 11 May 2023 16:10:56 GMT

Good point. I checked that. Slightly differnt result, but not really solving the issue. Does the point numbering somehow matter? At some point the surface apprears self-penetrating and knotted into itself.

Re: Unable to create surface patch

Gabriel_Watson — Thu, 11 May 2023 16:29:52 GMT

It's tricky. No self-intersections are allowed, and I think you might have too many points/sections on the boundary. I could wager someone will come in here and drop a comment about trying Fusion workflows first, and that might be a way out. Create this in fusion, then import it over to Inventor.

Re: Unable to create surface patch

johnsonshiue — Fri, 12 May 2023 00:24:41 GMT

Hi! Either Boundary Patch fails to create a smooth surface based on the selected closed loop, or there is a big gap in the spline. Please share the file here.

Many thanks!