Hi,
Currently, 3D sketches are very cumbersome to draw, especially for piping.
Although I have found a way, it is still much too cumbersome. (see screencast)
I can imagine to determine the path with absolute coordinate points, and optionally with relative values.
Since 99.9% of all arcs have the same radius, one should be able to specify a radius for all arcs without having to first select and round each corner.
The individual leg lengths and pipe elbows angles should be automatically measured, or at least to able to measure, which is particularly helpful for room arches.
At the moment the number of degrees can only be determined by measuring.
Michael