Scale a torus

How do you scale the radius of a torus? I saw this done in a video tutorial but don’t remember which one.

The simplest way with native tools is to redraw it, using FollowMe with one circle for the cross section, and another for the path.

Change the radius of the ‘tube’ in Entity Info, or the radius of the path in the same way, then re-run FollowMe.

Or you can use the extension SU Parametric 3D Shapes from SketchUcation plugin store. That allows you not only to update either radius ‘in place’ but also to choose the number of segments in either part of the shape - ‘tube’ radius or ‘path’ radius.

Sorry, I meant the radius of the tube of a torus.

Like this, using the extension:

Thank you I will look at Parametric 3D Shapes. Can it be done in artisan or vertex tools?

Possibly - I don’t use either so can’t tell you.

Seeing the image above makes me realise I need to update the extension - the InputBox should show Profile Segments and Torus Segments, not just Profile and Torus. It’s a bug in InputBox on the Mac, and I originally developed the extension on Windows.

I am on a Mac. Does the bug affect the tube radius?

No, just the text naming the variables.

Thanks John. I tried your Parametric 3D Shapes. It works fine but can’t use it because I need to keep the original number of faces for use as morph targets. I’m hoping to do it with Artisan or Vertex tools but still learning how to use them.

Just checking that you understand how simple it is to create a torus. Two circles and follow me. The radius and number of segments is totally under your control.

Thank you Box. Yes I know how to create and edit a torus with native SU tools. My torus will be scaled and manipulated to create shapes that retain the exact geometry as the original torus. I currently want to only scale the torus tube without adding or removing faces. I am making morph targets that will be exported to another 3D app.

I don’t understand this. You can set or change the number of segments in either sort of circle in the torus, in the plug-in.

What is ‘the original number of faces’, and why can’t you match it?

You can change either radius without changing the number of segments, and hence not changing the face count either.

The torus is one component of a master model. In order to create a morph target I can change the shape of the torus with any SU tool providing no new geometry is created or deleted. eg. Using the scale tool I can change the torus into an oval without gaining or losing geometry. I then save the model with an oval torus and name it morph target #1. I then go back to the virgin master model and make the torus ring thinner by compressing or scaling the mesh with the tool that I am looking for. I then save morph target #2. The Master model and all the morph target files are then exported to DAZ studio where the model can be morphed into different shapes and used as props in scenes that I use as art references.

John, I am having another look at your extension. The statistics of my torus shows number of edges and faces. Can I set these parameters in your Parametric 3D Shapes?

My Torus was made from a 6 sided polygon and subdivided. Maybe this is why your extension didn’t replicate the geometry.

It would help if you showed us some images of what you are trying to achieve as there may be a very simple way to do it.

Thanks to Box and John I have solved the problem. The problem was that I created theTorus with an extension when I was playing with quads and subD. There is a simple way as Box suggested.
I made a torus as illustrated by Box. And thanks to John, I was able to scale the tube with John’s Parametric 3D Shapes.
Thank you Both