Made a couple of tori.
Redid the waist for the red one, with blend.

Tutorial please? How did you do this? I've been scratching my head for a week on a blend like this.

Here's a quick one:



It will be cool to see how bemfarmer did his...

Burrman does the creation so quick and easy. :-)
I spent 20 times as long manipulating circles and semicircles, points, lines, booleans...
Once the semicircular edge is finally created, the blend is easy.

Hi Bem,
Well, I just slapped stuff together.... Usually, you are a geometry guy though... Did you create a specific shape of some sorts? If you did, I would love to hear what it was and what that setup intent was... Maybe just an overview?

Thanks.

I'll try to put something together. It is real late now.

Reminder: (As previously explained on the forum,) the "surface blend" is made from Edges, not curves.
The semicircle curve is used to create the semicircular edge, then the semicircle curve needs to go away, leaving the edge
for the blend... (hopefully this reminder is not too mangled...)

Something like this ?
Fillet G2
Of course any form can be drawn first :)

Funny method

Cool solution Pilou...

Peace,
Rich_Art. ;-)

Then extrude variable following wishing results
any mixed variable Fillets top bottom (G2) & / or Blends (G2) can be possible following acceptable values!

A partial tutorial. Borrowed ideas too. :-)

Most of the steps to create 2-torus:

1. (Per Pilou:)Do Circle, mirror circle, do tangent circle.
Intersect script, or place points
Edit trim, and mirror little curve.

2. Do Vertical circle for future torus sweep.
Mirror circle, do line and trim to make half circle, for future blend.

3. Remove old green circle, do arc.

4. Sweep half circle and line, with cap ends.

5. Remove fender shape, keep red area, delete curves.

6. Re-Form left circle.

7. Sweep little circle to form torus.

8. To remove part of torus: Do Boolean Diff of torus, with the red
area as the subtract selection. (Do not use red edges or red curves, or
the Boolean does not work.)

9. Cleanup, remove half circle curve, and small circle. (Edit Pictures for 8 and 9 are backwards...)

10. Select top two half circle EDGES (not curves), and do G1 or G2 Blend.
Mirror the Blend to the bottom.

11. Cleanup, and select 4 edges for planar. Repeat for bottom.