Help with patch?

Hi, I am trying to make a Y-branch shape.

I would like to patch the curves on the layer “PATCH?”
But I am not sure why the surface turns out so distorted.
Would someone please have a look at it, and add some suggestions how to do it?
Alternatively I have tried to do a workaround with netw srf-command,
but this is not as desirable in this particular project, and is also with a problem with the joining edge.

Any comments and suggestions in general how to do this Y-branch shape is welcome, thanks :slight_smile:

Y-branch.3dm (372.5 KB)

@pascal - any suggestions?

Here’s another approach:

Thankyou very much, i will try it out.
I was hoping for some method I could build with curves, and later modify the surface(s) by editing the curves or curves through points (Explicit history ex.)
The project is for a playground sculpture with many branches, and it would be best to be able to nudge around all the surfaces, to create a coherent, organic composition in the end.

Hi Ohlers - given the shapes you have, I think I might start off with something like the attached and then build the ‘trunk’ off of that.

Y-branch_Start.3dm (327.1 KB)

@ohlers There’s one more curve at the top that I used and did not make red, and I made a quick try at the ‘trunk’ - download again…


no worries - I got it
very nice method thanks!
after your first sweep2, i did a simple straight curve across edges
project to surface
and then a new sweep2 and join

very quick and perfect for what I need.

Thankyou ! :slight_smile:

Y-branch_Start finish.3dm (363.5 KB)

OK - I used NetworkSrf so that I could include the curves at the top/apex of the section curves.


OK - I will post update here with the project :slight_smile:

so far so good - its a nice method, using Pull to get the right Trim curve on the first surface.
The branch is also now netw srf, using curve through pts with history, to edit the surface after the netw srf command.

by the way… I would suggest that Rhino introduce a new command, a variation to
"Curve: interpolate points"

I can draw an interpolated curve , simply by clicking on other curves, right ?
We could call those clicked positions for "intersection points"
and the curves that I clicked on, for "intersecting curves"
The data for the intersection points are defining the new, interpolated curve.

But if i then nudge any of the intersecting curves, the interpolated curve remains unaltered…
And I would have to redraw it to get intersecting curves again.

I think it could be very cool, if the interpolated curve would be updated, when nudging the intersecting curves, and thus get the same effect, when drawing curves through points, with history.

Only, you wouldnt have to draw a bunch of points first, you could just very quickly draw intersecting + interpolated curves.

I know this is possible in “Grasshopper”, but for my workflow its a bit overkill to open a “Explicit History” session just for a few curves here and there…

You could call this new command: Curve: Interpolate “sticky” points :slight_smile:

thanks Hans Henrik

Right, this is how to get at this now - move the points with ‘Near’ on the intersecting curves. I think your proposed tool would simply place curve edit points only at the ends and Int points with the cross curves. Currently, Edit Points for an InterpCrv snapped to other curves do show up on the intersecting/cross curves, so you can turn on edit points (EditPtOn) and slide them with Near on the cross curves and maintain the intersections - the problem is the ends of the InterpCrv have one extra edit point each that does not fall on the intersections you snapped to.


This is cool ! I only know a fraction of Rhino - but it never ceases to amaze me !
‘EditPtOn’ + ‘Near’ will definetely be my new favorite :slight_smile:
You can also slide end points with ‘Near’

What about an IntPtOn command? (Intersection Points On)

Yes that is correct

oh, and ‘insert edit point’ is helpful too

Should we move this talk of Intersecting curves to a new topic?

This post covers several approaches to your modeling project. Surface problem- making a crown