Revolving 2D object around 2D Polyline failing

[tylerdurden]

Im trying to revolve a 2D polyline object around its bottom line (see photo). To create an axis for revolution (bottom of the 2D object), I have tried using the offset command and also manually creating an axis that matches the contours of the bottom the object to be revolved. The picture shows the axis, however, the axis I am actually trying to use is only offset about .001" (trying to get it as close as possible). When I try to revolve the object, I get an error "The object should be on one side of the axis". But the object IS on only one side of the axis, I have checked the entire length visually to make sure. Now if I use an offset of say .1", then it works, but that doesnt give me the 3D object I need. I have all the smoothness settings pretty high, 10000, 100, 10, 32, but changing these does not help. I tried scaling the object and axis larger (100x's), then offset would be .1 instead of .001, however that failed also. HELP!!!

[f700es]

can you share the file?

[CarlB]

You can only revolve around a straight axis not a curving polyline, if I understand what you're trying to do.

[tylerdurden]

can you share the file?

send me a message w/your email address and I'll email it to you.

[tylerdurden]

You can only revolve around a straight axis not a curving polyline, if I understand what you're trying to do.

are you sure? i dont get any errors revolving around a non-straight line if the axis is not too close to the object being revolved.

[CarlB]

Well I'm not entirely sure but AutoCAD help says when you select object to revolve around it uses a line or a segment of the polyline you select. So I tried it and that's what I found as well.

It also doesn't look physically possible to even offset your shape about the axis without interference (the sharp outside radius looks less that the revolve radius), which would also cause problems with revolve, if it is even possible to revolve about a curved axis.

[fenyess]

i think it is PHISICAL imposible that you revolve this object in to this axis.
why not extrude one circle in axis path...

[tylerdurden]

Well I'm not entirely sure but AutoCAD help says when you select object to revolve around it uses a line or a segment of the polyline you select. So I tried it and that's what I found as well.

It also doesn't look physically possible to even offset your shape about the axis without interference (the sharp outside radius looks less that the revolve radius), which would also cause problems with revolve, if it is even possible to revolve about a curved axis.

I didnt read that part about "uses a line or a segment of the polyline you select", but that would mean that it can only revolve around a straight line. However, it is possible to keep the curves seperated by increasing the radius of the curves by the distance you want the axis from the object (I've done this already perfectly). But doesn't look like that will matter if AutoCad can't revolve around a curved axis.

[tylerdurden]

why not extrude one circle in axis path...

What do you mean? I was trying to figure out how to do something like this, is it possible? I was trying to modify a cylinder into the shape of the curve, similar idea to what you're talking about...

[tylerdurden]

I got it, thanks fenyess, that worked perfectly. Didn't know you could extrude along a path (axis), thanks a ton!