Bugs in sketches

[michallach81]

Hi, I'd like to report two bugs.

First is related to this topic: http://forums.autodesk.com/t5/design-and-documentation/setting-orientation-along-a-3d-spline/m-p/566...

Sweep along helix like curve is not working properly, here is screencast how it should work (Onshape), and how it's actualy work in Fusion: http://autode.sk/1dOz2H4

In original topic I was pretty sure that jroddds build his profile on a wrong plane, and that was causing unwanted twist, but I was wrong, unfortunately something is wrong with either sketch or sweep.

Second bug is offset tool in sketch environment, just watch this: http://autode.sk/1FVQHWz , same bug you can see in Jesse Urban vid, it's even more obvious : https://www.youtube.com/watch?v=nvKRb5oHwnQ&feature=youtu.be&t=552

It's a problem not only with ellipses, any shape can cause problems for offset tool.

[Phil.E]

Your second case is logged as FUS-18090.

The first case requires a different expert. 🙂 Stay tuned.

[Phil.E]

For problem #1:

Regarding the video, the same effect can be seen using Coil command inside Fusion to create the elements of a similar 3D sketch and twisted sweep. 🙂 No import required.

The trip through Onshape is a bit of an apples and oranges comparison. The STEP output converts the helix shape to a spline curve. It's not the  same curve in Fusion due to translation.

Aside from that the real limitation in Fusion is the lack of a true 3D helix for a sweep like this. It might look the same as a spline curve but the math is different.

In the idea station, almost all of the ideas from this very early post have been built into Fusion.

http://forums.autodesk.com/t5/fusion-360-ideastation-request-a/3d-sketching-helix-sketching-construc...

This last comment pretty much sums it up, especially here:

"Thank you Fusion team! I really like the right click menu option to change lines to construction. It took me a few minutes to figure out how to make a 3D sketch, but I like the way you guys did that too. It is very intuitive after you figure out how to start. Could you guys give us the option to generate a 3d curve in the coil option instead of  geometry? It seem to me it already generates a curve, we just don't have access to that curve."

I didn't see a recent request for this, perhaps it's time for a dedicated Idea Station request for 3D helical sketch curves?

 *Thanks to Jeff S. for the great explanation!

[michallach81]

Hi Phil, as I mention in my post, I was somehow referring to problem that one of fusion users find tricky to solve. I'm aware of coli tool and how it works, but the guy was trying to make a coli with custom profile. My import was just to picture the problem we faced. I do belive that new helix curve will work fine, but in my opinion something is wrong with 3d curve already, it looks like 3d curve missing some value, to compute proplely. I've tried to sweep profile on a coils edge, also didn't work.
With my poor Engish skills it's a bit labor intensive, but I'm willing to write a post about sketches and patches, with some feedback and ideas. Main topic will be the sketch engine, I think that many bugs are caused by sketch engine, not that is buggy, just in compare with other softwares it has less capabilities. You've write:
"Aside from that the real limitation in Fusion is the lack of a true 3D helix for a sweep like this. It might look the same as a spline curve but the math is different." and I think exactly the opposite, any curve should give same result, tools like helix should simplify geometry creation, not introducing new maths.
Now about my "trip through Onshpe" are you trying to tell me that in Onshape I was sweeping along Helix, not just a spline??? Then if that is the case, I have a vid with reverse example: http://autode.sk/1IidpJn . This time it's only edge of "dump" geometry.
I know that you get a bit touchy if it comes to Onshape, but I favor Fusion over Onshape a lot. I even don't consider most bugs as a bugs, it's just the way Fusion works. I'm fairly confident with workarounds, that's way I'm trying to help other users with minor problems. I think Fusion is worth it some effort, and lack of some direct routes shouldn't push away anyone.
Exept my laguage, other reason I haven't posted already what's on my mind, is that I'm somehow aware of that reconsidering sketch engine may end up with totaly new engine. This will affect other modules... a hell of a work. We know how Fusion roadmap looks like, and I think most of users would like to see first new modules like sheet metal, S4D, etc.
In closing I'd like to say that I'm the true Fusion advocate. Great job (thumbs up).

[promm]

Michallach81,

Thank you for your feedback and ideas on sketches. Below is a post that Jeff put together explaining the history of our sketch solver. We are working very hard on improving our solver. We use feedback from users like you to help make sure the improvements are focused on customer experiences. I will use your example to investigate future coil and helix advancements.

http://forums.autodesk.com/t5/design-and-documentation/what-s-your-fusion-360-performance-like/td-p/...

Cheers,

Mike Prom