Trimming offset curves

[CNSZU]

Hello,

I'm having a very simple problem trimming an offset curve in sketcher.

Start with a circle, then offset that circle.
Now sketch two lines, one crossing the offset circle at the top, then another line crossing the circle at the bottom.
Last, "quick trim" the offset circle using the two lines. Note that the fist trim works fine, but when trimming the offset circle to the second line, an error message appears: "Cannot trim off middle section of an offset curve". I cannot figure out what's going on. Why would there be such a limitation and what can I do to successfully trim an offset curve using multiple curves?

Refer to the attached image.

NX8 E8800@3.7Ghz 6GB Quadro2000

 

[JohnRBaker]

This is NOT a 'problem', but rather it's doing exactly what you asked it to do, trim AN offset CURVE. That's what you did. But you can't 'break' an offset curve into TWO curves.

In this situation, you will either need to create a second offset curve, or do what many people do, if your profile is symmetrical, just model one half and mirror the other half (see attached video). This way you will still have only a SINGLE offset curve which means that you will have no 'problem' trimming it.

John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Industry Sector
Cypress, CA
Siemens PLM:
UG/NX Museum:

To an Engineer, the glass is twice as big as it needs to be.

 

[CNSZU]

Thank you, John, for the video describing a workaround, although it would only work with symmetry.

I'm still surprised why you can't break an offset curve into two or more curves since this is standard in cad packages I've worked with in the past.

NX8 E8800@3.7Ghz 6GB Quadro2000

 

[JohnRBaker]

It's just the way derived curves (such as offset) were designed. But if you think that this is a big deal, please contact GTAC and have them open an ER to this effect and it will be given consideration.

John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Industry Sector
Cypress, CA
Siemens PLM:
UG/NX Museum:

To an Engineer, the glass is twice as big as it needs to be.