Extend Surface

I’m having trouble extending simple surfaces in Rhino 6. I inconsistently have to enter either a positive or negative value to get the surface to extend the way I want it to. I never had this problem with Rhino 5.

Is the problem you are seeing similar to this:

Yes, that’s the issue I’m talking about. The trouble is, sometimes it extends rather than retreats if you enter in a negative value…but this is not consistent. I can have two surfaces, side-by-side, and one needs a negative value to extend properly while the other needs a positive value…did they fix it when you posted originally?

Hello - thanks - the relevant bug is probably this one


If you can provide an example with a surface or two that do not behave, I’ll add it to that bug track item.



Extend Surface Issues.3dm (1.3 MB)

Thanks, added to the bug item.


Sorry to revive such an old post but I’ve been slow to upgrade to Rhino 6. Curious if the extend surf. issue described in the thread was resolved? Just to recap, Rhino 5 had a nice dynamic extend surface functionality. You could pull the edge in positive or negative direction at whatever distance and it would accept it. Now it’s really fussy.

Hi Jeff - actually if did not. Which leaves me a bit perplexed…


Something is different with 6 than 5. What is it? When you are dragging the surface out it gets “hung” a lot more often.

Hello - well in V5 you do not get to drag the edge. That is a V6 thing. I would try SetBasepoint in V6, say to one end of the edge and see if you can get cleaner action that way. And/or post an example.


Went back to test V5 and you are right about the non-dynamic edge but its way easier than the current tool. In V6 the red circle with a line comes up all the time for no real reason. Setbase does help but it’s an extra step.

Hi Jeff - if you have examples that simply do not work in V6 and do in V5, please post here or send to tech@mcneel.com, with a link back here in your comments,