Easy Spirula Shell Form

[BallBearing]

Or almost. Perhaps there is faster ways. This has closed manifold & thickness.

[pilou]

Maybe this ?

[BallBearing]

It's a nice tool. I have used it, but not enough.

[TBoy]

Here is the best analogue I was able to make.

Use these steps:

1. Use "spherical helix (loxodrome)" plugin to make helix.
2. Take upper part of the helix and flatten vertices to zero with "Flatten vertices" plugin. (Flatten only if you want to keep horizontal symmetry)
3. Use "Tapper maker" with round section to extrude along curve - play with start/end radius to obtain touching turns.
   Not fast but looks close to needed shape.

[BallBearing]

I tried, but I feel this tapering more difficult for 3D printing (to have thickness & solid). Nice looking as a sketch anyway. And these tools are good. Or perhaps I did not find right procedure yet?