Pattern a feature that was extruded "Up To Face"

elizabeth_giovanardi

I am helping a student create a model of a suspension bridge. The path of the suspension cable is drawn as a parabola and swept.  Then I created the vertical suspender at the center of the bridge (highlighted in orange in the image) and extruded this feature "Up to Face", with the face being the sweep of the suspension cable.  This worked fine, then I tried to pattern this feature, hoping that it would continue to pattern up to the face of the suspension cable.  It worked fine for a certain distance from the original feature, but once I got far enough away, the pattern became the same extrusion length as the original, rather than finding the face of the cable.  Any ideas here?  I figured either it wouldn't work at all to pattern a feature up to a face that gets farther away, or it would work great, but this is some weird in-between space that seems illogical to me.  Below is a link on my YouTube channel showing it in action.  I got around the problem by extruding up to face and clicking on each of the circles (which is why you see the circles in the sketch) but I am wondering if this is simply a bug in the software?  Thanks!


https://youtu.be/JaQ8MbMT-Q8

bradley_sauln

Here is my approach: https://cad.onshape.com/documents/7f8d5cf4a5b2f5c5922ff538/w/9798d4c8b35afd5575543dec/e/dbc65e06a2066d5c25fd1ebd

I used "up to next" as my extrude option.

NeilCooke

Have you tried “Apply per instance”? That’s what it’s for. If that doesn’t work, extrude them blind and trim using the parabola path sketch. 

bradley_sauln

Here's a webinar that covers this pretty well. Jumping to 20:15 in has the info you are looking for I think: https://www.onshape.com/videos/patterns-in-onshape-04-20-17

elizabeth_giovanardi

@bradley_sauln
Thanks for the response.  I watched the video in its entirety and learned some things.  It pointed out that the feature pattern patterns the entire operation, so the fact that feature that I want to pattern was extruded "To a face" should make it so that each patterned feature does in fact extrude up to the cable.  This does in fact happen but only up to a certain distance away from the original (as shown in the original image).  The YouTube video that I linked shows the problem as I was working.
To investigate further, I changed the cross section of the suspension cable from circular to square, and the problem still existed.  I also created the first feature as the tallest suspender (again extruded "Up to face" or "Up to next") and then tried patterning it.  It never got the pattern correctly, as seen in this image.  https://cad.onshape.com/documents/6912ac7f018f616cbc2a7d5c/w/25753f2ec713402cba895fdf/e/d9ac36a324db8db13796b918

elizabeth_giovanardi

@NeilCooke
Thanks for the response.  You are correct that I should've tried that (I'm somewhat new to OnShape, coming over from Inventor). I just tried turning on the "Apply per instance" and you can see that it was ineffective.  Even though I requested 7 instances, it only created 2.https://cad.onshape.com/documents/6912ac7f018f616cbc2a7d5c/w/25753f2ec713402cba895fdf/e/d9ac36a324db8db13796b918

bradley_sauln

Here is my approach: https://cad.onshape.com/documents/7f8d5cf4a5b2f5c5922ff538/w/9798d4c8b35afd5575543dec/e/dbc65e06a2066d5c25fd1ebd

I used "up to next" as my extrude option.

elizabeth_giovanardi

@bradley_sauln
Yes that seems to work when I tried it as well.  I tried that iteration yesterday but I hadn't yet learned about the "Apply per instance" button that Neil had mentioned.  I am still curious why "Up to next" works but "Up to face" does not.  Hopefully there is not a time when I need one and not the other when then patterning.  Maybe it's a bug that should be eventually reported and fixed? Thanks so much to both of you for helping with this; at least there is a solution for this case!