Workplane is skewed

[Anonymous]

This revolved shaped is centered on the origin, however when I try to create a workplane or sketch off it it becomes skewed as shown above. How can I make sure my sketches and workplanes are centered on the origin?

[SBix26]

Attach your file here so we can see how you defined your workplane.  And tell us what version of Inventor you're using.

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Sam B
Inventor Pro 2020.0.1 | Windows 7 SP1
LinkedIn

[Anonymous]

I just updated to the newest version, Inventor 2020

[SBix26]

Your file doesn't include the skewed workplane, so how can we tell why it is skewed?

To center things on the origin, make sure your sketches make use of the projected origin point.  By default, this is projected into every sketch when it is created, and all you need to do is attach your geometry to it in a logical way.  Your first sketch in this part is attached to the origin, but not in a way that makes good use of symmetry.

In general, though, this part model seems to indicate that you're new to 3D modeling.  For example, all sketches are underconstrained.  How much training or experience have you had with Inventor or other 3D modeling applications?

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Sam B
Inventor Pro 2020.0.1 | Windows 7 SP1
LinkedIn

[Anonymous]

Hi I am still learning CAD. I've attached my updated file with the workplane. My first sketch was centered around the origin, that is why i'm confused why the workplane is being skewed

[Anonymous]

Hi I am still learning CAD. I've attached my updated file with the workplane. My first sketch was centered around the origin, that is why i'm confused why the workplane is being skewed

[SBix26]

Now I see what you're wondering about.  I don't know why the workplane is skewed relative to the origin, though it shouldn't matter because it's only representing something that is infinite.  But, I see that it does matter because starting a new sketch on that "skewed" workplane creates a coordinate system that is skewed in the same way.  That can be corrected, but it shouldn't happen to begin with.  @johnsonshiue , can you figure out why this happens?

Now, since you're a beginner in 3D modeling (note: usually when someone refers to learning or using "CAD", they're talking about AutoCAD or similar software), would you like to learn how this might be modeled better?  Is this a fantasy part, or is it intended to be manufactured, or is it intended to duplicate something that already exists?  In other words, what measurements do you have already vs. what are you making up as you go?

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Sam B
Inventor Pro 2020.0.1 | Windows 7 SP1
LinkedIn

[johnsonshiue · Accepted solution]

Hi Sam,

This is yet another common surprise in Inventor. This behavior has something to do with choosing sketch coordinate system on the selected face. Depending on the selected face loop and orientation, Inventor chooses the coordinate system based on an internal algorithm. In this case, there is lack of linear edge to attach to. As a result, the algorithm is doing something it thinks logical.

To avoid a behavior like this, the user can do two things. 1) Use UCS so that you always have a set of orthogonal planes to work with. 2) Finish sketch -> right-click on the sketch -> Edit Sketch Coordinate -> select logical vertices to realign the coordinate system.

We are aware of the wacky behavior and we are investigating solutions to make it better. But, we don't have a good solution yet.

Many thanks!

[Anonymous]

Thank you for the help! Editing the coordinate system did fix the problem