Circles and arcs

I’m doing some work for a friend involved in steel construction. I make a 3D model of something and where there are circles or slots, I make a 2D AutoCad dwg file to allow that piece of the work to be completed by a company using laser cutting. It seems that AutoCad makes true circles and arcs and my sketch files exported to 2D dwg is still segmented. Even if I use the Aaron / Dave technique of drawing in metres and making 7m radius holes with 360 sides and subsequently scaling down to 1/1000, it seems this isn’t good enough. Anyone else having / had difficulties like this please? Thanks

Export as a 3D. File > Export > 3D Model > DWG

2D output is always segmented. In 3D exports circles and arcs are exported as true AutoCad arcs and circles.

With 3D export to autocad:
By exporting the edges, the curves are smoothed
By exporting the face, the curves remain segmented.
This is why after export, the two types of curves are superimposed in acad.
So to get a clean export you have to go to the options and uncheck the export of faces

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Hi, I couldn’t find where to uncheck the export of faces and so I deleted the face and just exported the lines (a rectangle with two circles representing the holes). The dwg export that I can see using the Autodesk viewer still shows the circles segmented.prova.skp (161.3 KB)
I’ve attached the skpprova 2.dwg (23.6 KB) file called prova and the resulting dwg file called prova 2

export options

It isn’t obvious that to get a good export of a 2D DWG you need to use the Export 3D Model option, not the 2D one. Another benefit, beyond getting true curves, your camera position doesn’t matter. You will get a correct scale top down export. With 2D exports you need to switch to parallel projection and a top down view, to get the correct size.

Thanks. I’ve got a 2D dwg image from a 2d skp file exported using the 3D option that seems to do the trick.

I’ll send it off to the laser cutters and hope for the best.

I’m very grateful for the collaborative help of everyone.

Problem solved with fingers crossed. Thank you