Exaggerating curve

I am making bending forms for bending wood. The forms must be silghtly exaggerated, since the bent wood springs back a little bit.

Is there a tool that I can do curve radius exaggeration with a constant factor?

Maybe your experience in bending can tell you the extra amount needed and then just make curves to follow your rule.

Hi woodman- can you provide an example or two of starting and desired over-bend curves?


Thank you for reply!
Here is a one example curve. Bending wood is not 100 % excact science, but what I have experienced, is that all radiuses should be exaggerated about 10-14 % for bending. When using a circle arc, it is easy to just draw smaller circle. But what to do when the curve is more complicated?
All ideas are most welcome :slight_smile:

I have used FLOW ALONG CURVE tool to “add” circle arc to the original curve. It is not perfect, since it just adds a constant bend all over the curve, also the straight part. What would be perfect method, is to multiply the radiuses by same factor. but how…

Hi Woodman - I guess you’d also want correspondingly more degrees in the arc, so to speak, as well as a smaller radius, if you are over-bending. Could you provide a rhino file with some typical curves in both designed and over-bent state that work for you in real life?


Hello! Unfortunately I do not have files like that, yet… But the general ida is that for instance when you have bending form which is 100 cm diameter circle, you will get 110 cm diameter bend in wood. works linearly, so with 50 mm D form you get 55 mm bend.