How do I trim intersecting surfaces to each other?

[jakewells]

I am trying to trim the two surfaces below to each other, but have not had any luck using the following methods:

- projecting the brown curve onto the purple surface and using that as the triming curve
- extruding the brown curve and using the resultant surface to trim the purple surface
- applying all types of booleans

The surfaces are simple: one is a lathed powersketch with 4 control points, and the other is an extruded powersketch with 4 points.

http://www.jakewells.com/trimsurfaces.jpg

The file is available at http://www.jakewells.com/trimsurfaces.zip

Thanks!
Jake

[nPower_Dave]

I am trying to trim the two surfaces below to each other, but have not had any luck using the following methods:

- projecting the brown curve onto the purple surface and using that as the triming curve
- extruding the brown curve and using the resultant surface to trim the purple surface
- applying all types of booleans

The surfaces are simple: one is a lathed powersketch with 4 control points, and the other is an extruded powersketch with 4 points.

http://www.jakewells.com/trimsurfaces.jpg

The file is available at http://www.jakewells.com/trimsurfaces.zip

Thanks!
Jake

Hi Jake,

Do those 2 surfaces intersect at the corner (as they appear to)? You might try the merge option and then delete the excess faces.

[jakewells]

I can do that, but it leaves more edges than the two per face I would expect, which leads to problems with sewing and filleting ...

[nPower_Michael]

It is hard to tell from the picture, but maybe the two surfaces aren't lined up sufficiently accurately at those corners, and you might be getting some extra 'mini-edges' as a result. Have you tried to extend the surfaces a little (either through recreating them or by railsweep, etc) before the merge?

I tried to create similar geometry; I created one profile curve with end points on the world x axis, and extruded it to get the yellow surface; then I created another profile curve with snapped end points, and rotate-cloned it about the origin. I blended the two curves to get the purple surface. Then, I bool-merged the two surfaces and subtracted faces, and it gave a mostly reasonable result (2 edges per face, and looked good; however the fillet tool didn't like the degenerate blend surface). What construction did you use?

[nPower_Michael]

Oops, I missed the fact that you posted the Max file; sorry about that.

I've opened up the file, and I used Boolean Merge operations with imprinting, and it looks like the two surfaces are indeed not quite lined up. On one side I got a tiny little extra edge, and on the other, the surface didn't get split out all the way to the vertex. That being said, because some of the angles are kind of close, it looks like resnapping things to make this work may be difficult; one thing that did seem to help was to extend the extrude a little towards the revolve.