serious loft bug

[cekuhnen]

I never experienced the ability of a loft command to skin profiles / edges I did not select.

Fusion can do that 😉 of course should not

you cleary see the edges I have selected

The loft is going clearly to the wrong edge

[TheCADWhisperer]

I didn't figure out exactly what was going on, but I was curious why-

are you using surface modeling to model simple primitives?

and

I experimented a bit and was surprised to discover that Fusion will not create a trimmed patch by selecting multiple profiles, it would only let me select a single profile and no "islands".

So then I tried trimming the planar Patch with the cylindrical surface, but it would not trim.

I extended the cylindrical surface and I could trim both surfaces (attached in untrimmed state).  Might be an alternative technique.  Might look closer at why it wouldn't trim without first extending (I assume there is no intersection - a gap - even if microscopic, I didn't investigate further).

[cekuhnen]

each cylindrical solid was made via the solid revolve tool and then combined.
Later in the design timeline I noticed that trimming went bad and there I saw that the solid combine was flawed rather joining the solids into a bad geometry and not really trimming and creating a real solid.

That is when I backtracked and did the rebuild by hand and then I found the loft bug.

This are so basic bugs - it makes Fusion really hard to use.

[jakefowler]

Hi Claas,

Good spot - I haven't seen anything like this before (please do send similar examples if you have any). I've sent this to development to try to get this fixed.

Many thanks for reporting this & attaching the file, this really helps!

Jake

[jakefowler]

Hi Claas,

The development team have told me that it appears as though an earlier operation appears to have caused some internal information to be 'lost' from the model. Do you remember the steps you used to create this body up until the point where loft encountered this issue?

Many thanks!
Jake

[cekuhnen]

There is a major bug in the system here.

I can reproduce it - but this time the wrong edge is the long cylinder.

Look at the two blue edges selected but how the loft command skins.

https://drive.google.com/file/d/0Byzv_NlyKp_2NTRrZTM4VGd5cGM/edit?usp=sharing

Interestingly this time the second solid revolve command with join trims the internal faces correctly!

[cekuhnen]

The bug can be reproduced even when I make revolve solids from a sketch and then unstitch and loft gain.

Check attached file and video:

https://drive.google.com/file/d/0Byzv_NlyKp_2LVo3ZFlrZjJJemM/edit?usp=sharing

[cekuhnen]

Just for the sake of testing

I created a sketch two rectangles

created solid revolves

unstitched

relofted and same bug

Timeline Solid Revolve

No Timeline Solid Revolve:

Did a nother quick test with patch revolve and the bug does not apear

so I would say the solid revolve causes this.

Doing this in DM or TL makes no difference

[jakefowler]

Many thanks Claas, looks like this was enough info for the development team to track it down. It turns out Unstitch was the culprit - we'll try to get this one fixed soon.

Really appreciate your help with this,

Jake