I had never tested the Offsetsrf function to generate an extrusion, I usually use the extrusion of curves or surfaces. When I do this, I always rebuild my polycurves (built from arcs and segments), precisely to avoid having “joints” in my generated extrusion. I do this when I have to apply curves on developments (=unrolled surfaces) of curved stair stringers. I also do this when I need to use the “interpolate on surface” function to get a smooth curve on the curved surface. I attach an example file that was discussed in another discussion.
From now on I will test the Offsetsrf function directly on my curves to check the operation.
Overall, this proves that you have a choice of functions to achieve your goals, even if you have to know them!
I agree with you about editing attached curves, it can quickly be boring for simple 2D drafting functions.
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railing.3dm (1.1 MB)