Lofting Rails

[TheCADWhisperer]

Edit the Loft feature in the attached file to examine how it was created.

Now delete the feature and attempt to create the same loft using the 3D Rails sketch rather than the 3D Center Rails sketch.

Should it be expected to work either way?

I am able to select on or the other of the 3D curves (in 3D Rails sketch) as a rail, but not both and not with the 2D curves.

[innovatenate]

I can reproduce the issue, but I'm not sure about the behavior. Perhaps there is a limitation to the number of Rails (non-centerline rails) that can be located in a single sketch. I will forward to the development staff for review and let you know what I find out. 

Thanks,

[sdpatil]

Hi,

Actually in this case when you select any sketch curve from "3D Rails" instead of "3D center Rails" its forming a centerline instead rail. Because to form a Rail there is a condition that the selected Rail/s should touch and 'end' at the last profiles (and also touch in-between profiles if any). It should not go beyond end profiles. Otherwise it will be treated as Centerline. 

There can only be one centerline at a time for loft. So as soon as you select other curve and if fits to the definition of centerline, previous centerline gets de-selected automatically. If it identified as rail then first centerline will get deselected and current selected curve will be taken as Rail. In the attached image we can say AB will be treated as a Rail and AC as a centerline.

I hope this answers you query. Please feel free to let us know in case of any other doubts.

[TheCADWhisperer]

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@sdpatil wrote:

Hi,

 Because to form a Rail there is a condition that the selected Rail/s should touch and 'end' at the last profiles (and also touch in-between profiles if any). It should not go beyond end profiles. Otherwise it will be treated as Centerline. ..... 

So go ahead and use the 3D Center Rails Sketch AND the Bottom and Top Rail sketches.  These two sketches do not meet your condition, yet the Loft works.

[sdpatil]

Ah, I see.

Yes, Sorry for the confusion. It’s my mistake. I apologize for the inconvenience caused. Actually the condition for Rail is : it should touch the boundary of all the selected profiles. There is no any restriction on number of rails. It’s ok if it extends beyond end points.

Here there seems an issue with the projected and 3D curves. It’s not giving the proper intersection with the selected profiles. We will surely look into this issue and improve it accordingly.

Thanks for raising the concern!