EXTRUDE TO INSIDE OF SHELL

[Grroberts]

3 hours ago  Status: GATHERING SUPPORT

Extruding to inside of shell 

I am attempting to extrude to the INSIDE of a shell but the extrusion carries through to the OUTSIDE of the shell.The problem seems to occur when part of the sketch is tangential to the surface, (see screenshot), because in other cases the extrusion happens as expected. IDEAS?

When the shell is of uniform thickness it is easy to set an offset but if the inside surface is not uniform it become complicated

 

EXTRUDE TO INSIDE OF SHELL.png ‏306 KB

[Grroberts]

I am attempting to extrude to the INSIDE of a shell but the extrusion carries through to the OUTSIDE of the shell.The problem seems to occur when part of the sketch is tangential to the surface, (see screenshot), because in other cases the extrusion happens as expected. IDEAS?

When the shell is of uniform thickness it is easy to set an offset but if the inside surface is not uniform it become complicated

 

EXTRUDE TO INSIDE OF SHELL.png ‏306 KB

[Anonymous]

I'm not getting a clear understanding of your issue. Can you possibly attach an F3D file?

[Grroberts]

Thank for the interest, I have included an amended description of the
problem
Gordon

[TrippyLighting]

Where ?

If you are replying to threads via email, attachments do not come through. You'll have to use then web interface to include attachments.

[Grroberts]

This is a revised description of the problem

Gordon

[chrisplyler]

Is the purpose of this to get, for example, the top of a bottle to fit inside a cap, or some similar condition?

If so, it might just be easier to extrude the body of the bottle on up through the cap, and then do a Split Body on the bottle using the inside faces of the cap as the splitting tool, and then Remove the excess bits of the bottle.

The example below is overly simplistic, and could have been done easily with Revolves. But I did it with Split Body which would allow a more complex, non-symmetrical result if necessary.