wing tip split.3dm (127.3 KB)
Rhino 8
How to edit or split a single surface? Needing to split the attached file into 2 symmetrical halves or remove one half along the XY plane. Nothing I’ve tried has any affect.
Thanks
What have you tried? Is the surface locked?
Method 1:
Split using the Isocurve option and select the isocurve of the surface on the XY plane.
Method 2:
Use Plane command to create a surface on the XY plane which passes through the surface to be split.
Use Split command with the plane created to split the surface into two halves.
Method 2:
Use Plane command to create a surface on the XY plane which passes through the surface to be split.
Use Trim command with the plane created
Method 4:
In the Front or Right viewport use the Trim command with the Line option and ApparentIntersection=Yes.
use DivideAlongCreases on the object first and check both options, splitting then works. though that surface is not really well modeled. also the singularity on one side will be problematic. i would rebuild that entirely, keep it as simple as possible.
You can use Rhino’s Split command with the Isocurve option, splitting in the U or V direction, as shown below.
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Method 1 works for what I need. Split command with the Isocurve option.
Variations of method 2, 3 and 4 didn’t work the way I was trying. I’ll dig into those later tonight.
Thanks
I agree the surface is not well modeled. Attached is the basic cross sections that need to be lofted or swept around the tip for a smooth transition from a rounded leading edge to more of a sharp trailing edge. I welcome any input as to how to get a better surface. Thanks
wing tip loft.3dm (128.7 KB)
anytime anyone asks about howto improve their surfaces, I take the opportunity to share Sky’s primary surfacing video series. Must watch for anyone wanting to make better models.
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Lots of wing-tips on the forum over the years. You could try the approach below. Here’s also a guide about basics to take on board for NURBS surface modelling.
Wing tip again.3dm (2.1 MB)
First of all, once you understood NURBS curves reasonably well, it would be a good idea to redraw the existing “pieced-together” curves, as the current ones have discontinuities.
This is how you could start cleaning up the top view. Then proceed to the sections. You only need to do the upper half of the wing by the looks of it.
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Are you modeling an existing design, or is this a new design?
If it is an existing design what information are you basing your model on?
If it is an existing design how accurately does your model need to match the existing design?
Existing design.
Blueprint from 1962.
Very precise. Ultimately the surface will be a carbon fiber shell over a wooden structure. The ribs in the simple file that was attached is exactly as the blueprint shows.The wing tip curve that transitions around the trailing edge has been adjusted very slightly to intersect with the rib chord end points. The leading edge rearward angle and the overall span needs to stay unchanged. The ribs could be adjusted in thickness slightly to gain a smoother surface, but not their chord. When the max ordinate of each rib is connected it is along a curve, not a straight line segment from rib to rib. New rib profiles could be extracted from the final surface.
The original 1963 hand drawn half scale blueprint is “pieced together” using arcs and then a curve through multiple points to fit the span, leading edge angle and rib chords. Fudging here and there with the pencil is apparent. The dimensions usually rounded to nearest 1/16” inch. Maybe more.
