Pipe intersection using a trimmed surface (sheet metal)

[Anonymous]

Hello,

I encountered a problem when I noticed the thickened surface is overlapping with a surface I used for trimming. I hope the attachments can help figuring out what I'm trying to say.

What am I doing wrong here? Is there a way to work around this problem?

[JDMather · Accepted solution]

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@nikkevixd wrote:

What am I doing wrong here? Is there a way to work around this problem?

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Well, your sketches aren't fully defined - but that isn't the problem.

You haven't really done anything "wrong" other than you have to make engineering decisions that will account for real-world.

You are doing digital prototyping that revealed a legitimate issue. You will need to adjust hole size or whatever else it takes to allow assembly of the components. And keep in mind that we cannot manufacture perfect parts - so allow some realistic manufacturing tolerance for clearances.

This is the beauty of 3D modeling - we can discover these types of issues before they get to the shop floor and make necessary decisions.

[CCarreiras]

Hi!

But you understand why it overlaps, right?

Well, to finish overlaping, you can model like this, but the question is: How you gonna Produce/Cut this pipe?

it's already a pipe, or is a rolling sheet metal?

[Anonymous]

Hello,

Thank you both for your quick replies.

JDMather, I find this really interesting and I'm hoping to learn a lot more. Thank you for helping me out again.

ccarreiras,

Database schema for the file is newer than my version, it seems. I can't get it open. I'm running Inventor 2016.

The sheet metal is going to be rolled, yes.

I can only guess the reason behind overlapping but I'm not 100% sure of this. I'm really interested in hearing more of this, please.

[JDMather · Accepted solution]

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@nikkevixd wrote:

I can only guess the reason behind overlapping but I'm not 100% sure of this. I'm really interested in hearing more of this, please.

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When you do Thicken the thickened face is parallel to the original surface and the edges are perpendicular - just like the real world sheet metal (sides are perpendicular to the flat).

This trips up a lot of people when they get into sheet metal.

Do this -

Create a Shelled cone with a thick wall thickness.

Now create the same part with the Sheet Metal Contour Roll feature 

and/or with Thickened surface.

Notice any difference?

[Anonymous]

Hello,

The shelled cone seems to be flat on top and bottom surfaces but the thickened surface one seems to have an angle on top and bottom surfaces.

The perpendicularity to the flat seems to be the cause of this? The extension seems to be equal to the tangent of the used angle times thickness.

[JDMather]

Looking at this result - do you understand why Shell does not result in a proper sheet metal part for a cone.

You intersecting tubes are a more complex example of material thickness rolled from flat.

[Anonymous]

Shell doesn't create a flat pattern with perpendicular edges. Flat pattern made of shell doesn't match with the real world sheet metal.

You have been a great help. Thank you so much!