topic Re: Loft is unusable for simple shapes in Fusion Support Forum

Loft is unusable for simple shapes

Anonymous — Fri, 22 Jan 2021 22:21:27 GMT

The video describes it well, but essentially, every time I use the loft, I receive a different result than what is shown in the preview. To add to that, I can't actually manipulate the markers or the loft will always fail - if they are not supposed to be moved at all, make then unmovable, this is confusing (I know I should use rails, I just wanted to quickly bodge something together).

Also hollow lofts are not a thing. Dunno why, in my head I can perfectly imagine a loft doing what I wanted it to, but I guess it isn't really an issue for something this simple. For more complex shapes it would be great though, because one might have to resort to making 3D sketch paths and using sweep.

Re: Loft is unusable for simple shapes

jhackney1972 — Fri, 22 Jan 2021 22:25:21 GMT

~~Your video did not attach to your post.~~ Loft cannot create a hollow object. It takes two lofts, one for the solid and one for the hollow cut. Video showed up after awhile.

Edit: Please attach you model so the forum users can trouble shoot if for you.

Re: Loft is unusable for simple shapes

Anonymous — Fri, 22 Jan 2021 22:39:38 GMT

Yep, edited the post right after I posted it cause It didn't attach due to "HTML errors"... sigh.
That was kind of a minor issue that I noticed a while back and wanted to know if that's intended or not, the other two issues are likely not intended.

Re: Loft is unusable for simple shapes

Anonymous — Fri, 22 Jan 2021 22:38:31 GMT

Sure, here is the file. It should work, but I did export it before I even saved it, I literally just started on the project.

edit: btw, using rails of course does fix it, so I'm not looking for a solution, I'm just reporting a possible bug. This is how it should look like (done with rails)

Re: Loft is unusable for simple shapes

davebYYPCU — Fri, 22 Jan 2021 22:40:41 GMT

Screencast took two goes, John.

Loft is finicky, simple fix, but as said, hollow lofts have never been possible. Always a second cut loft.

Edit / change the diametre of the circle in profile 1 to force the correct rails.

Might help.....

Re: Loft is unusable for simple shapes

jhackney1972 — Fri, 22 Jan 2021 22:50:59 GMT

About the HTML error, when you touch the HTML icon, make sure you have the cursor on a blank line before you paste the code you will never get an error. The two points you used to size the circle create the extra surface rails so just drag them to the corners and it works great. As I mentioned before, Loft will not create a hollow body period, it take two lofts to do that.

Re: Loft is unusable for simple shapes

davebYYPCU — Fri, 22 Jan 2021 23:11:10 GMT

Finicky and not a correct solution earlier. I missed that the sides were not the same as the top / bottom results.

Yes moving the mapping handle in preview is not retained when confirmed.

@jeff_strater this gremlin should be looked into.

To get the correct result I reduced it to 1/8 profile, 1 Loft (no longer hollow), mirror and pattern.

Might help.

Re: Loft is unusable for simple shapes

TheCADWhisperer — Sat, 23 Jan 2021 13:05:42 GMT

As an aside to all of the other responses - I thought that I might point out that geometrically that is not a simple shape.

Re: Loft is unusable for simple shapes

jeff_strater — Sun, 24 Jan 2021 19:53:53 GMT

[edit] - never mind, I just didn't go back far enough in the thread to see the first post. Weird. I'll capture that one

[edit 2] - Fusion bug is FUS-77510

@davebYYPCU - can you explain exactly what doesn't work? I tried a simple case and it seemed as if the point mapping was correctly preserved.

Re: Loft is unusable for simple shapes

davebYYPCU — Sun, 24 Jan 2021 22:08:47 GMT

I refer you to my pic in message 5.

The side faces with two mapping handles near parallel can not be reproduced on top and bottom faces. You can place the rear handle points in position, but will not stick when pressing Ok.

This shape without rails may not be possible, with Op’s Geometry as it was, but the top / bottom mapping handles do move to the location needed, but Fusion reverts on Ok.

This (each) corner area needs 3 mapping handles to get to the Op’s Request, (soft transition)

(we cant add a handle for rear corner point to midpoint of the arc, in preview stage)

but Fusion will only provide 2.

I didn’t try both mapping handles to the mid point of the arc, only thought of that as I am writing this.

I got there because it needed a tunnel as well by going another way.

John’s response was to make the sides the same as the top / bottom, but doesn’t address the mapping handle problem in the Op’s videos

Might help.....