topic Re: Surface Extend Valid Object Types in AutoCAD Forum

Surface Extend Valid Object Types

harliY432P — Sat, 08 Aug 2020 19:55:26 GMT

Hi All,

Can anyone please explain was surface extend is not working for any of the outside edges of the attached file?

I understand it is a region, but even using convtosurface and then doing an extend doesn't do the trick?

Thanks

Re: Surface Extend Valid Object Types

harliY432P — Sun, 09 Aug 2020 07:32:34 GMT

I found a work around. If the file is exported as an Iges and imported then it works.

I'll mark this as a solution if no one has another idea.

Would like to know why the file doesn't work in it's original form though.

Re: Surface Extend Valid Object Types

j.palmeL29YX — Sun, 09 Aug 2020 07:58:43 GMT

The surfextend command needs a Surface. You have drawn a region, this is a not allowed object type for this command.

But you can convert the region into a Surface using the convtosurface command. Now surfextend will work if you pick an edge of the Surface. Be aware, after convtosurface you have two overlapping obects - the region and the new created surface. (Delete the region or move it away or be carefuls while picking the correct edge).

Re: Surface Extend Valid Object Types

harliY432P — Sun, 09 Aug 2020 07:54:47 GMT

Thanks j.palmeL but as per my original post. When I use convtosurface it still doesn't work.

Re: Surface Extend Valid Object Types

j.palmeL29YX — Sun, 09 Aug 2020 08:26:39 GMT

Read again please. In the meantime I edited my first answer.

>>Example_Video<<

Re: Surface Extend Valid Object Types

SEANT61 — Sun, 09 Aug 2020 09:44:29 GMT

The Region in the initial attachment has experienced corruption somewhere along the way. I’d guess that the Region’s brep has an opposite winding than usual. See screencast.

A recent capability enhancement to AutoCAD has been the sub-object selection method for 3d Solids and Regions. Now a CNTRL + Select can isolate features to those entities to allow Move (Extend, and even Erase if subentity is moved off the entity), Scale, Rotate. No Copy, unfortunately.

Regions may have desirable qualities (MassProps) not available in Surfaces.

https://knowledge.autodesk.com/community/screencast/749ed8af-8f61-4c34-b92b-35bf0e421461

Re: Surface Extend Valid Object Types

harliY432P — Sun, 09 Aug 2020 09:50:44 GMT

Excellent reply, thanks for the help Sean and Jurgen. I suspected that there was some form of corruption in the region. The problem is that I have plenty of them so the original work-around of exporting to iges and then reimporting does the trick nicely.

Jurgens approach (convtosurface) only works on a few objects (the example file being one of them that it works on).