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Full Version: Creating a planar surface from a 2d curve results in strange unfilled geometry

From: quat
4 Sep 2022   [#1]
I'm having some very strange issues trying to use the planar command on an enclosed curve made of a couple arcs and polylines glued together with the join command.


I've got this curve here that I'm trying to make into a plane. It's fully enclosed, all one singular curve, and entirely two-dimensional:


But, when I try to fill it, or extrude it, I get this strange, inadequate approximation:


You can see here that the BREP is not being accurately represented by its sloping edge:


As you may have guessed, working with geometry like this down the line is next to impossible. This shape refuses to boolean or fillet. I have attempted multiple times to remake this curve with varying techniques, but have achieved similar results.

I've been asking a few questions recently, I'd like to take a moment here to thank everyone who responds to these. With that being said, Am I misunderstanding how solids work in MoI?
Thank you in advance.

Image Attachments:
wing1.PNG  wing2.PNG  wing3.PNG 


From: bemfarmer
4 Sep 2022   [#2] In reply to [#1]
Hi quat,
I think that it is a display artifact, due to display speed compromises.

Try Options > View > Mesh angle , lower value, say 2, or 5, ..
See Michael's response.

- Brian
(Post a .3dm please)
From: Michael Gibson
4 Sep 2022   [#3] In reply to [#1]
Hi quat, that is just a display artifact where the display mesher did not generate a lot of triangles in that area.

It's purely a cosmetic display issue, it doesn't mean anything is wrong with your actual object.

That type of display glitch can tend to happen more when you have a shape that is only very slightly curved across a larger area, as you have here.

Just ignore that particular thing.


> This shape refuses to boolean or fillet. I have attempted multiple times to remake this curve with
> varying techniques, but have achieved similar results.

The shape refusing to boolean or fillet is due to some other issue, please post the .3dm model file so I can take a look at it.

- Michael
From: quat
5 Sep 2022   [#4]
That makes so much more sense now. Thank you!

Also, regarding the issues I was having with the geometry itself:
Taking a break and looking at it again made me realize that I had managed to repeat the same mistake each time I made the shape. I'd accidentally made the rounded front curve just barely non-tangential to the bottom surface, which made it stick out on the bottom a tiny bit. This seems to be what was causing the trouble.

Again, thank you for clearing this simple issue up. This forum is a life saver.