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Why does this Ruled Surface fail?

Hi onshape forum!
I'm trying to create a ruled surface and it fails. I cannot figure out why it does and I'm currently unable to figure out a workaround.
I'm referring to the last feature in this document (a simplified recreation of my issue):
https://cad.onshape.com/documents/e979d6d1d47d1d9e94efecbd/w/7c9cc67840120426cdf86a80/e/38e7b897b5f2552e38beecaf
Any insight would be appreciated!
Best Answer
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S1mon Member Posts: 3,616 PRO
Ruled surface is not liking the two "poles" of your original revolved surface. I suspect that it gets confused by the degenerate nature of the surface there.
I trimmed the poles out, and ruled surface works.
Depending on what you need to do next, you could create some lofts or boundary surfaces to fix the missing pieces.
Simon Gatrall | Product Development Specialist | Open For Work
1
Answers
Hmmmm … I can't see. It is read only, so it cannot be edited or rolled back to be analyzed. It is not even clear what the ruled surface was meant to be.
@martin_kopplow I've changed it to public, sorry about that. The ruled surface was meant to be a normal surface around the edge of the shown surface. Cheers
Ruled surface is not liking the two "poles" of your original revolved surface. I suspect that it gets confused by the degenerate nature of the surface there.
I trimmed the poles out, and ruled surface works.
https://cad.onshape.com/documents/3ab00b53b48995bdbd161116/v/8f86a8b56e8be9a2a956d263/e/779ed4de834f8b4b334c010b
Depending on what you need to do next, you could create some lofts or boundary surfaces to fix the missing pieces.
Simon Gatrall | Product Development Specialist | Open For Work
@bernhard_petri
Okay, I looked at it, but am not sure what you're trying to achieve. It appears you might want to recreate a surface you already have. What is the intention? If you want a straight connection between the two swirled curves, a loft might be an option. It will always be tricky with the two curves meeting at such a pointy angle at both ends, though.
Without these pointy ends (cut them off to isolate the issue), your settings would have returned someting like this:
https://cad.onshape.com/documents/dcc988a5b1d3a081990eb2f5/w/6f059eebfcf72f73cb8b696a/e/249ee8634c320d44cdb463ee?renderMode=0&uiState=682e02d7baaca1543b37e25d
You could have achived this in full length and with one click by means of the thicken tool. Just delete the inside face later.