curviLoft help from square profile to circle profile

attached is a file with a square base and a circle above it. I tried to loft between them to make a tappered conical type shape and the loft gets all twisted. Im still learning this extension.

loft practice.skp (292.2 KB)


Try doing one quarter at a time:

Curviloft/Skin contours

Accept the result:

Rotate/copy three times:

Hide or soften the hard lines, and remove the extra quadrant edges on the top and bottom surfaces.

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ok, so i need to skin it rather than just loft it. I was trying to move the vertex points around during the loft opperation and it became messy even faster haha. Its intersting how some lofts work but others dont

For myself, I most often use the Skin Contours option in Curviloft, and rarely try the other Loft options.

But you need to make sure the ‘contour’ to be skinned is a continuous single curve with no gaps and no forks or stray short lines - the Skin Contours then fails.

If this is what you were wanting to do, please mark my post as the Solution.

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that is what i wanted. thank you:) i am now going to try the skining feature with more spline type rails

did you draw lines from the circle down to the sqaure


Yes - radial lines top and bottom to split the top and bottom perimeters to create a quarter, then two lines top to bottom - shown selected in orange in the image you posted back.

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You already have the guides, why not use them.

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yup, this is how i did it:) I used the guides. Just wasnt sure if the other poster drew lines down or how it was done. I was hoping the loft feature was going to work the same way. I have used the skinning feature once now with this example and partially with a mask example.


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thats a nifty feature. kind of like follow me but for lofts.

Yes, it allows you to tell it what path to take between faces.
Along path


thats nice. I am now going to try and make a more bell type lines from the square to the circle. One of my favorite loft shapes from the basic curvi loft option is the eliptical one.

it creates a cool shape but since i cant get the curvi loft basic to work, i have to figure out how to dra the actual lines:)

follow path

the follow path does not like curved lines haha

That sort of shape should be a skinning, 4 curves and skin.
Curviloft is very versatile but it has to understand what you want to do.

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Like most of Fredo’s tools It has so many possible results it is a life’s work to fully understand it’s uses.
More options

I really like the tool. So far its doing some stuff i like, just need to learn the ins and outs of this extension.

How do extensions like this work? Juat use native tools really fast in the background or is it other stuff?

They basically automate what is ‘possible’ with native tools.
A very naive way of putting it, but the code tells sketchup what to do and it can only do what is possible. It cannot make unsegmented curves for example, it works with the same geometry but with more access to algorithms and such computer stuff.
As I have never written any code in my life I’m most likely talking out of my bottom.


I refuse to code. I can math and physics all day but not code…

So technically you could loft the mask ibmade with native tools?


Theoretically yes, but it would require a lot of accurately placed curves and a lot of hand stitching. Or a lot of moving and scaling. It is just a web of edges, you simply need to know where to put them…

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