Hi Rudl, or maybe another possibility is that you want some result where the offset is made more by expanding the original shape along some distance along the averaged direction from the original vertex point? That produces another different kind of shape in the result where there would be somewhat different thicknesses between every set of planes rather than a totally constant distance between every piece... CAD offsetting tools are more oriented around keeping the thickness between surfaces constant rather than trying to make a constant distance between the resulting corner vertices.

So there are a few different variations in what kind of result you might be looking for, you will need to sort of nail down what you are looking to achieve a bit more specifically I think.

If you want 90 degree side walls and a constant surface thickness, I believe the output from TurboCAD may be that result, that's the one where there will be some change in vertex structure in the offset piece.

- Michael