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# 1 07-07-2013 , 03:27 PM
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Trimming NURBS and Boolean Difference Issues

salam,

i attached a PDF with images that show the problems

I started learning Modeling (Maya 2013) and I want to model a Technics SL-1210 MK2 Turntable (Image 1). I tried different modeling techniques but they all lead to a problem in the end.

First I used polygonal modeling with boolean differences for the cutouts in the body of the Technics (the holes where the turntable, buttons etc are placed in). (Image 2)
When I want to bevel the Edges of the boolean difference, parts of the mesh disappear/become invisible (Image 3). Reassgning the shader doesnt solve the invisible mesh, and after deleting the history the beveling still doesnt work properly

So I tried it with NURBS. I project curves onto the NURBS surface, I increased the Curve Precision and the Crv Precision shaded under the NURBS Surface Display attributes, so my circular curves get projected correctly (Image 4). But when I extrude the trimmed egde, i get a low res and facetted extrusion. I used a linear CV Curve for the extrusion.
So under Tessellation I tweak the Simple and Advanced Tessellation attributes, but the extrusion stays low res. (Image 5)


Why is the extrusion not connected to the trimmed egde? When I convert to Polygons to combine the meshes in order to bevel the edge, the extruded mesh got more vertices so I cannot connect it correctly to the surface-
Is there no way to bevel a trimmed egde and keeping the NURBS ?

I think NURBS is the appropriate modeling technique for this object, is this correct?

What do I need to consider if I want to use this turntable for realtime purposes?

Attached Files
File Type: pdf Modeling Issues.pdf (171.3 KB, 582 views)
# 2 07-07-2013 , 09:22 PM
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I don't use nurbs mush so I will answer your question about polygon modelling, the reason you are having problems with your Boolean is that you are not cleaning up the mesh after the Boolean. Edges need to connect to other edges so you have clean edge flow.................dave




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# 3 08-07-2013 , 01:55 PM
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thank you daverave.

indeed i didnt clean up the mesh afterwards. Is this the problem : when I subtract a polygon torus with lets say 80 segments from the surface (which is only one single polygon), this creates 80 unconnected edges ? how to solve this then? I thought it would create a n-gon

i think for this object its better to work with NURBS ?

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