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akelly12-Amethyst
12-Amethyst
March 29, 2021
Question

Total Unroll Cross-Section (un-fold along an arc)

  • March 29, 2021
  • 5 replies
  • 3904 views

Using CP4.  This is probably more of a 3D modeling issue, however, I've labeled it as 2D drawing because that's the final target.

Is there any way to create a Total Unroll cross section?  Cutting lines would include an arc, like the attached image.  But I want it flattened / un-rolled along the arc in the drawing.

I created an offset section with an arc per the arrached offset section.  It will show the section in the drawing as a true projection.  The un-fold option is grayed out.  Section arrows show up correctly (with the arc).

Total Unroll Cross-Section.jpg

5 replies

tbraxton
22-Sapphire II
tbraxton22-Sapphire II
22-Sapphire II
March 29, 2021

Is the view you are attempting to unfold a projection view? Try creating a general view and apply the section to the view. Do not use this view as a parent to any projection views once you get it working.

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akelly12-AmethystAuthor
12-Amethyst
March 30, 2021

No. It is a general view.  Full Unfold section type is grayed out.

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MartinHanak24-Ruby III
24-Ruby III
March 29, 2021
@akelly wrote:

Using CP4.  This is probably more of a 3D modeling issue, however, I've labeled it as 2D drawing because that's the final target.

Is there any way to create a Total Unroll cross section?  Cutting lines would include an arc, like the attached image.  But I want it flattened / un-rolled along the arc in the drawing.

I created an offset section with an arc per the arrached offset section.  It will show the section in the drawing as a true projection.  The un-fold option is grayed out.  Section arrows show up correctly (with the arc).

Total Unroll Cross-Section.jpg

Hi,

I guess that you cannot unfold x-section containing arc, because such functionality is not implemented.

A
akelly12-AmethystAuthor
12-Amethyst
March 30, 2021

so I was hoping someone might have an idea for a work-around?

tbraxton
22-Sapphire II
tbraxton22-Sapphire II
22-Sapphire II
March 30, 2021

If I understand your goal, you want to flatten a cylinder to present it in a drawing view. In that case there is a work around by using flatten quilt. Here is an example of a cylinder surface flattened so it can be shown in a drawing view. I have used this in the past to present timing diagrams for the cylinder of 2 stroke IC engine designs to document the porting and timing of the design. Creo 4 part posted for reference. You need to pay attention to where Creo is splitting the circle in half relative to how you want to develop the surface.

 

Flatten quilt used to develop cylinderFlatten quilt used to develop cylinder

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akelly12-AmethystAuthor
12-Amethyst
March 30, 2021

For clarification, this would be the 2D opposite of the 3D Wrap. I've used wrap to apply labels, graphics, etc. to curved surfaces of a part.  So in this case, I just want to un-wrap the 3D solid, surface, line, point, etc. geometry for a 2D drawing view.

 

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akelly12-AmethystAuthor
12-Amethyst
March 30, 2021

I tried merging the part into another part, cut out the material below the section line from my cartoon, then using the Warp feature with the Bend operation.  Maybe it's not possible or maybe I was just using it wrong, but I couldn't bend the (now) C-shaped part straight.  Got lots and lots of bad geometries.

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mvitárius15-Moonstone
15-Moonstone
March 31, 2021

Is it possible you want sheet metal function?

mvitárius_0-1617186461441.png

 

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akelly12-AmethystAuthor
12-Amethyst
March 31, 2021

I thought of that, but it doesn't work.  At least not the way I tried.

 

I created a new sheetmetal part.  Then tried to merge the solid into it.  It wouldn't allow me to merge because the source part was solid.

 

There's nothing in this part that could be confused with a flat/formed sheetmetal.  It's machined (milling/turning) from solid bar stock. But un-rolling the cylinder to a flat view of the "inside" has engineering value.

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