topic Re: Sketch rotates 90 degrees when sketch plane angle is changed in Fusion Support Forum

Sketch rotates 90 degrees when sketch plane angle is changed

brink.gregory — Sun, 08 Mar 2020 23:05:43 GMT

I have a sketch on an angle plane that is defined by a user parameter. The sketch rotates 90 degrees on the sketch plane when the sketch plane angle with respect to other construction planes is changed. I've tried using a sketch plane at an angle, a plane through 3 points and planes through two edges. There are some differences in the point of rotation with the different options but they all rotate plus or minus 90 degrees on the sketch plane (with respect to the original sketch orientation and the XZ origin plane).

Some of features on the problematic sketch are referenced to features defined on other planes so it seems like they're all being ignored when the the plane angle is changed. I also added some sketch constraints to features in the origin and other planes but none of these strategies have been successful at keep the sketch from unintentionally rotating.

I searched the forums and found some posts that were dealing with similar issues but they were a few years old and seemed to leave the situation as a known bug.

Is there a way keep the sketch from rotating 90 degrees on the sketch plane when the angle of the sketch plane with respect to other construction planes is changed?

Is there a work around for this problem?

Re: Sketch rotates 90 degrees when sketch plane angle is changed

davebYYPCU — Sun, 08 Mar 2020 23:22:35 GMT

You have the context as to why the sketch was not there in the first place?

Work around is to copy / paste to a second plane / sketch, hiding the original.

Might help...

Re: Sketch rotates 90 degrees when sketch plane angle is changed

brink.gregory — Sun, 08 Mar 2020 23:44:15 GMT

I've done some additional experiments. I made a simplified model with two offset construction planes and a sketch plane on an angle referenced to a line on a sketch on one of the offset planes. Changing the user parameter angle works correctly with no unintended rotation of the sketch on the angled sketch plane.

I went back to the design and found an origin-like symbol on the angle sketch plan that seems to be the point about which the sketch rotates when the sketch plane angle user parameter is changed. I can't find a way to move or change the sketch plane origin.

How can the location and rotation of the sketch plane origin be controlled?

Re: Sketch rotates 90 degrees when sketch plane angle is changed

davebYYPCU — Mon, 09 Mar 2020 00:19:37 GMT

That is in loose terms and where it can be done - is a projected file origin (offset planes).

Where it can't be done practically, it seems this (origin / base) icon

is where you clicked to identify a location when making that type of plane.

for example that dot will be on the first selected point of a 3 point plane, disregarding the file origin.

Plane on angle on a line will appear at the mid point on the line you selected.

Note these icons are only visible when there is a sketch on this new plane.

Using a plane for split body, it's not there.

Might help....

Re: Sketch rotates 90 degrees when sketch plane angle is changed

TheCADWhisperer — Mon, 09 Mar 2020 11:56:42 GMT

@brink.gregory wrote:
Is there a work around for this problem?

Can you File>Export and then Attach a *.f3d file here that exhibits this behavior?

I have an idea for an easy work-around, but would need to test on specific geometry.

Re: Sketch rotates 90 degrees when sketch plane angle is changed

brink.gregory — Wed, 18 Mar 2020 19:04:02 GMT

Thank you for your responses!

The problem began after I realized that the angle plane I originally defined wouldn't yield the desired result. I moved the sketch to a new plane using the redefine sketch plane tool. That's where the design was broken. The sketch and associated bodies would rotate 90 degrees when I changed the plane angle. Very bizarre considering it happily made the 90 degree rotation without complaining about all of the constraints to features on other planes and the origin that were broken.

I deleted the sketch and the plane but new planes and sketches still behaved the same way. It seemed that the bug was somehow stuck in the model. I tried the suggestions above but I was spending more time trying to fix it than it would take to start over. So, I cut my losses and began again from scratch.

My remaining question is this: Is this behavior a known bug or a recurrence of a bug that was thought to be closed? It's not clear to me how to report bugs to Autodesk. Are the forums the right/best way to give feedback to and receive support from Autodesk?

Re: Sketch rotates 90 degrees when sketch plane angle is changed

davebYYPCU — Wed, 18 Mar 2020 20:13:27 GMT

As I understand it, this is implemented behaviour.

Like you have found, avoid it like the plague,

better to start over than even try to use / understand it.

Expect the Unexpected!

At least when pasting a sketch we get the option to align.

There are threads that explain it,

There was even a video singing it’s praises, but that simple example used a circle (on its own) in its sketch, have never forgotten that rotating a circle 90 / 180 degrees did not break the sketch, hence the guy figured it was working ok. Don’t know if it has been taken down by now.