G1 Error lofting with Rails

[Anonymous]

I was on here a few weeks ago and received some great help, actually where I learned of the sweep with rails feature, and I am now using loft with rails (with some success at least). I have tried searching the form and although I have found some posts regarding the G1 error, I have not found any solid definition of the G1 error and the solutions have not be successful when applied in my models.

I am trying to use a loft with rails command to create a form. I was successful at this with one model, but when the same steps are repeated on other models it gives me a G1 error. Unfortunately I do not know what this error is trying to tell me. I have tried changing multiple things to get it to work but have failed on all attempts.

I am using 3 rails on three different planes, two of which are angled planes to help keep the triangular shape throughout the form where needed. I will attach all three of the files. "chubgrub" worked fine without issue. "Flicker" has a G1 error, and "stanko" had a G1 error as well as some mysteriously disappearing lines that are detectable only by hovering over them. For some reason today without changes, it still has the disappearing lines but now but now says avoid self intersections. 

I'm not sure if this is an issue with my workflow in trying to create these shapes, or the complexity. Or if its just something that I'm simply overlooking.

Any help, or direction at what I should be doing differently would be greatly appreciated.

[laughingcreek]

In both cases you have rails that aren't tangent(G1) between every segment.  Rails must be tangent along their entire length.

but you can still do this by swapping your profiles for your rails.  in the attached i've added a line to the "worm" sketches to make them closed profiles.  I then used the profiles for the loft, and used the circles and sorta triangles for the rails.  no other lines where added.

[Anonymous]

I'm on a work computer without fusion so unfortunately I can't view the file right now. I do appreciate the quick response. I didn't know the profiles and rails would work in reverse like that. Pretty neat.

Also this doesn't make a lot of sense to me. On a different project I had an error stating that profiles couldn't be tangent, and the loft wouldn't work because they were. I put coincident constrains on all of the profile and rail intersections. Should I have used tangent instead?

[TrippyLighting]

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@Anonymous wrote:

..On a different project I had an error stating that profiles couldn't be tangent, and the loft wouldn't work because they were. I

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The error you have was that the profiles could not be tangent to the rails and that does make sense most of the time. Occasionally Fusion 360 returns this error when it does not make sense..

The coincidence constraint where rails and profiles intersect is definitely a good this and a prerequisite to be able to loft.

Tangency is required between the sketch objects in a rail.

In Flicker if you select the vertical sketches as the rails then there is no tangency between all the individual arc segments. But there is tangency between the sketch objects in the triangular sketches. So I you use the triangular sketches as rails instead of the vertical ones than its work at least as a surface loft.

[laughingcreek]

The "profiles can't be tangent rails" error usually means  the rail is tangent to the profile where they connect.  sometimes it just means there is something wrong and you have to hunt down the problem.  If you post the problem someone can help you hunt down the problem