topic Re: Cutting body with hybrid modeling in Inventor Forum

Cutting body with hybrid modeling

Anonymous — Thu, 14 Dec 2017 12:42:55 GMT

Hi,

I've created this cylinder:

I've then modeled a solid as a separate lofted body:

I have then deleted top face and it turned to a surface body. I want to cut the cylider using the split command (solid cut) but Inventor doesn't accept surface body that was generated after deleting one solid body face.

I then modeled a revolved surface body from scratch:

In this case split command accepts it:

What's different in the surface body that was generated after deleting one solid face that doesn't make Inventor accept it as a selectable surface body in the split command ?

In attach is the file.

Thanks,

Re: Cutting body with hybrid modeling

jhackney1972 — Thu, 14 Dec 2017 13:23:22 GMT

When you delete a face from a solid, it really does not turn the solid into a usable surface, as far as the split command is concerned. What you have to do is copy the solid surface into a true surface using the Copy Object command, then it can be used as a split surface. Using this method I am still having trouble splitting your example solid I think because of the odd shape you have lofted. Even if I loft a true surface using your geometry, the split cannot be created. Take a look at the Screencast.

Re: Cutting body with hybrid modeling

JDMather — Thu, 14 Dec 2017 13:30:45 GMT

I am not sure why surface body created by Delete Face is cannot be selected with Split, but it does work with Sculpt.

Of course, there is easier way, (Loft Cut or Combine-Subtract come to mind) but I am assuming this is a simplified example only for the purpose of investigating Split behavior with surface body resulting from Delete Face.

Re: Cutting body with hybrid modeling

WHolzwarth — Thu, 14 Dec 2017 13:34:52 GMT

I made a similar approach like John, and got a result.

2018 IPT attached

Re: Cutting body with hybrid modeling

JDMather — Thu, 14 Dec 2017 13:38:40 GMT

@jhackney1972 wrote:

.... Even if I loft a true surface using your geometry, the split cannot be created.

Must have planar surface to close hole at bottom of lofted surface.

Re: Cutting body with hybrid modeling

johnsonshiue — Thu, 14 Dec 2017 14:07:31 GMT

Hi Alex,

This is like a bug or limitation. Split anticipate a surface body or a workplane as the tool to cut. Deleted face solid is indeed a surface body but it is kind of like in a transient state to become a solid body again. It is why it is painted in solid color not the surface color. Anyway, the behavior is indeed inconsistent with other surface accepting commands like Sculpt. Let me work with the project team to find out if this limitation can be removed easily.

Many thanks!

Re: Cutting body with hybrid modeling

Xun.Zhang — Fri, 15 Dec 2017 02:56:40 GMT

Hi Alessandro,

Appreciate for the feedback, and ticket INVGEN-12062 was open to track it down.

Thanks again!

Re: Cutting body with hybrid modeling

Anonymous — Fri, 15 Dec 2017 19:32:44 GMT

Thank you John,

I didn't know the body is not a usable surface.

I was used to systems where you had full flexibility to model with an hybrid solid-surface approach.

It means they're interchangeable: delete a face and you'll get a surface, do some surfacing, then trim and knit bodies and create a solid again.

Re: Cutting body with hybrid modeling

Curtis_W — Fri, 15 Dec 2017 19:40:26 GMT

Hi @Anonymous,

Another option would be to use the Combine tool to subtract the conical body from the cylinder. In the Combine tool you would want to select the "Keep Toolbody" option. Once subtracted you could then turn on the conical body's visibility, and then use Delete Face as needed.

I hope this helps.
Best of luck to you in all of your Inventor pursuits,
Curtis
http://inventortrenches.blogspot.com

Re: Cutting body with hybrid modeling

Anonymous — Fri, 15 Dec 2017 19:42:17 GMT

Thank you all for your help. It seems that sculpt makes the job.

I was indeed looking for a command that would perform a "cut with surface" operation.

The split command also does a "cut with surface operation" so I agree it should allow you to select that surface body as well.

Alex