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Slick trick for force closing a sketch profile in FS?

Stormi_BackusStormi_Backus Member Posts: 36 PRO

My company recently switched to OS from Alibre so I am re-vamping all of our configurators with FS. This went super well for roller chain sprockets/bushings but I am struggling with welded steel and pintle chain sprockets because the mathematics in the ASME are JUST imprecise enough to prevent a closed sketch profile. We're talking 0.000000 - OnShape can't even measure the distance between the point and circle highlighted below. 

I found a way around this by using configurations instead of featurescript as you can see here, but my coworkers vastly prefer having the FS in their toolbar over having to insert a configuration. 

So, I am wondering, does any one have a slick trick for forcing a closed profile in featurescript? Maybe there's something obvious I am over looking? Any solution I've thought of wouldn't hold true from part to part. Thanks! 


  • Jacob_CorderJacob_Corder Member Posts: 114 PRO
    can you share the document?

    It is likely that fill will still close it.

    if the edges that are supposed to be touching, do not meet at a vertex, then it gets more complicated.
    If they do meet at a vertex, you can modify the arcs, lines by just creating a new sketch with the existing geometry's data. if it is a spline, its safe in this case to get the bspline curve and just adjust one of the end points to meet correctly.  

  • Stormi_BackusStormi_Backus Member Posts: 36 PRO
    @Jacob_Corder there is a link to the document below. Please note that the current FS is a partially-constructed cob webbed graveyard I abandoned a few weeks back when I realized I wasn't going to achieve a closed profile. The element of concern is the three point arc between the Cp bounding lines. It should arc along the larger DB circle with end points intersecting the two smaller construction circles. 

  • Stormi_BackusStormi_Backus Member Posts: 36 PRO
    You can see what I was working towards if you open the sprocket body sketch in the "Variable Driven Part" tab. 
  • Jacob_CorderJacob_Corder Member Posts: 114 PRO

    I cant even find what you are referring to in the model. 
  • Stormi_BackusStormi_Backus Member Posts: 36 PRO
    I think I asked this question before I was ready...I will explore @Jacob_Corder's initial suggestions and follow up here once I am more prepared for a solution. Thank you for the help and patience!
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