# Move cuts in Solid geometry?

Hi all,
Perhaps a silly question, but is there any command that can move a cut geometry on a solid, like say, rotating the selected groove (pictured) some degrees, while keeping the solid an intact solid?

// Rolf

I think in this case you can just explode, rotate and join to get a polysurface again.

I tried that, but unless I didnâ€™t do it right, only the grooveâ€™s surfaces moved, and left a hole behind, as I expected. I assumed that there would have to be a special Rhino function to do something such.

Just to be clear, I have N grooves but would like to move them individually, which means I cannot rotate the whole surface (the surface has other geometries as well).

// Rolf

Have you tried the MoveHole command? Iâ€™m not on a 'puter at the moment and I havenâ€™t tried that on a sphere before as far as I recall.

EDIT: scratch that one - it only works on planar surfaces. Would have been cool, thoughâ€¦

Itâ€™s a ball ache but you can explode and rotate the walls to where you want them and retrim in the new location and then Untrim the original holeâ€¦

Hi Rolf

Any reason why you cannot close the old hole by Untrim and open the new hole by Trim or Split ?
Maybe too long ?

Looks like this works with SubObject Select and rotateâ€¦ Just ctrl/shift select the edges and you can move or rotate them.

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Interesting, but I get extreme deformation when trying this

// Rolf

Ouchâ€¦ I gathered from your original post that your section was circular. I tried it and it looked fine, but your new post doesnâ€™t look circular. In that case, youâ€™re back to more complicated methodsâ€¦

It was circular, but after the move itâ€™s no longer circularâ€¦

The problem may be due to other geometries on the sphere that must not be moved (well, otherwise I could just have rotated the whole sphere).

// Rolf

I want to say, make sure youâ€™re rotating from the center of the sphere, but there must be more to it.

I tried several times just to make sure just that

// Rolf

Can you post the model or weâ€™re just guessing from screenshots

Did you rotate only some of the control points for the sphere? If so it will distort.

Simplest way to move the groove:

ExtractSrf the surfaces which comprise the groove.

Rotate the extracted surfaces to the new postion.

Untrim or UntrimHole the hole in the sphere.

Trim the sphere with the groove surfaces.

Join the groove surfaces with the sphere.

Guessing right isnâ€™t a bad thing.

No problem with the model. Simplified:

Ball Joint Simplified - Move Groove.3dm (734.4 KB)

// Rolf

Hmmmâ€¦ See what you mean.

I guess Iâ€™d copy the face border and then rebuild the curves and then loft, extend the surfaces and recut holes. Use the copy face border command again then, explode, untrim the surface and use the curves to delete the bits I didnâ€™t want in order to tidy up the surfaces.

As far as your request to move easily - Iâ€™m not sure there is one

Ball Joint Simplified - Move Groove.3dm (760.8 KB)

[quote=â€ś2DCube, post:16, topic:35526â€ť]
your request to move easily - Iâ€™m not sure there is one[/quote]
At least the tips about Untrimming will help a lot (why didnâ€™t I think of that?).

Thanks to all that tried.

// Rolf

Perhaps are you thinking of your model in terms of a â€śsolidâ€ť instead of as a surface model that encloses a volumeâ€¦

From a newbie like me, â€śnot knowing what tools are in the box as of yetâ€ť is probably a better description. From that perspective the technical solutions behind the model doesnâ€™t really matter, given the assumption that what trivial stuff can be done manually can also be done automagically (tool box again).

But yes, I am very aware of the surfaces-enclosing-a-volume kind of solids in Rhino, which I think is a very good thing, since one can switch between the two approaches at any point in time. Thumbs up for that solution.

// Rolf

Not quite AutoMagically but at least easier to change on the fly if you are in a process of form-finding for an object and donâ€™t mind doing some work up-front: extract all surfaces in Grasshopper and rotate and stitch at will:

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