Hi Kevin,

> See my original post for a file. You can see the error on the scaling rail when zoom in
> at the big end. All osnaps were on when drawing the scaling rail curve.

When I examined your file, I do see an error in the sweep surface on the big end, but I can't really see any osnap error in the scaling rail not touching the end profile there, it seems to end right on it... But like I wrote above it's not necessarily the _profile_ that the scaling rail has to cover, it's a set of planes that come up from the rail curves that the scaling rail has to cover.


> Perhaps I need to zoom in more when drawing my curves and the "on" osnap would work better ?

It can be a bit easier to control things in general when zooming in, but it shouldn't make any difference for whether "on" snap is on a curve or not - when you get on snap the point should definitely be on a curve...

Could you please give some more info on the snap error, right now I'm not understanding it.

- Michael