[ANSWERED] Create lobed knob / Sweep along "wavy circle"
Document with all the tries in separate part studios: https://cad.onshape.com/documents/7d92ebfc4d42d67498b44c02/w/c3e079a016e5604e415d2895/e/8d83e605f9727daac7ef5c4f?renderMode=0&uiState=671eb1542b083d3d38a744a6
Any help on this would be greatly appreciated.
It is kind of tricky to put into words what I want to create, so here are two pictures of the kind of knob that I want to model:
My initial idea was to sketch the circumference using straight lines and arcs like so
…then thicken the core and sweep a semicircle along the outside perimeter.
This however only succeeds if I select three or less segments of the perimeter, otherwise the Sweep won't work and say "Lock direction causes invalid geometry" (even though I never selected lock direction anywhere.
I was able to kind of get what I wanted by separately sweeping the straight section, then a curved one and cutting off the "excess". The result of which I could put in a circular pattern.
This does seem like a very odd way of doing it, though.
Best Answers
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I would always strive to create only one section of this geometry, cutting off excess if required, and putting that in a circular pattern. that is definitely the way to go.
That way if you add a fillet to the edge, Onshape only has to calculate that once and can just copy afterwards.
perhaps a loft with a path is the way to go for spanning the gap between two 'straight' sections.
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Here is an example,
I didn't spend much time on this, and finished form should probably be adjusted (but it demonstrates the workflow).
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Answers
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@felix_fischer992 - You might try this approach, revolve the basic round form, sketch necessary geometry required to cut one flute, sweep cut that shape one time , then circular pattern that sweep cut feature (don't forget to check the apply all instances box)
Good luck
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I would always strive to create only one section of this geometry, cutting off excess if required, and putting that in a circular pattern. that is definitely the way to go.
That way if you add a fillet to the edge, Onshape only has to calculate that once and can just copy afterwards.
perhaps a loft with a path is the way to go for spanning the gap between two 'straight' sections.
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Thanks a lot, that works a lot better and produces a result that is close enough to what I want.
I don't think it is perfect yet, since the knob in the pictures looks a little different, but it will certainly do for my purposes!
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Here is an example,
I didn't spend much time on this, and finished form should probably be adjusted (but it demonstrates the workflow).
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Tank you for the example, I didn't quite understand your approach before but now it is clear to me.
This looks like the best way of doing it.
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