Adding draft to a STEP file

I have a STEP file that has to be modified to include draft angle for injection moulding. This is the kind of work I do regularly and have always modelled new surfaces from scratch. This always gives me exactly what I want but it is slow and therefore quite expensive.

So my question: is there a tool or method in Rhino that can add draft angles to existing geometry, in a similar way to Solidworks? I have played around with the Taper tool but the results haven’t been quite what I wanted, it seems to do odd things to radii for example.

I’ve discovered that I do have a few blind spots when it comes to tools in Rhino (despite using it for years) so thought I’d consult the experts :slight_smile:. Thanks for any suggestions offered.

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Hello - as a general answer, no, there’s no tool for this… But I suppose depending on the exact situation, it might be possible to come up with some shortcuts.


Hi Pascal, thanks for your response. It’s always good to know that you haven’t been overlooking an obvious solution, even if that means the only way to do it is rather slow and tedious.

I’m curious about the shortcuts you have in mind. I can’t share the file, unfortunately, but I could probably find something similar. It’s basically the B surfaces of an injection moulded part - think ribs, bosses and small fillets everywhere (but no draft).

ExtrudeTapered for example, if applicable.

However, as Pascal indicated, there is no global draft tool as in some MCAD platforms.

Often, you can take advantage of symmetry or repetition so that you don’t have to make the same thing more than once.