Why won’t these surfaces join?

Rhino
1

These surfaces share a common line of edge points. They are both degree 3 surfaces
join query.3dm (685.4 KB)
Why won’t they join?

Join query
Join query2560×1390 235 KB

2

because they are not touching each other.

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to solve it, you can use the Extend Surface Command to extend them like the below:

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then use the Intersect command to generate a common curve that can be used to trim both surfaces.

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then trim these surfaces

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and finally you can join them

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3

Hello- I would just move the single control point at the tip of the red decking to the end of the blue surface edge that is right there - that is the only thing out of whack.

image

-Pascal

4

Thank you Pascal. I should have found that. I spent literally an hour searching and researching for the problem and, as usual, it turns out to be finger trouble.
Kind regards,
Hugo.

5

maybe mark pascals answer as solution - there is a checkbox below the post - so others don t need to dig into the topic. … happy modelling -tom

6

Hi Hugo - CrvDeviation or EdgeContinuity > Position can help in these cases - showing where the biggest gap is.

-Pascal

7

Thank you Pascal. I have never used these commands before. Using them would certainly have saved me a lot of time and prevented me from showing my ignorance :face_with_diagonal_mouth: