Thanks to Davide Tirindelli for a great tutorial.
Add-on: Add Curve: Extra objects
Add Curve > Curve Spirals > Archemedian
Spheric, Turns: 4, Steps: 24.
‘Mark Root’ a start vertex for each separate curve cluster or separate objects.
CTRL-B or subdivide to add more control points
Press Smooth to smoothen hand drawn curve (using extend vertex).
CTRL-A to modify thickness of skin.
Proportional editing works with CTRL-A
You can use this to reduce the thickness of the spirals)
Convert to mesh
Delete faces and bridge edges to connect
Do not use Inset on faces where thin bar connects with thick bar and fuse it all together.
Instead, keep as separate objects to allow for separate Bevel on each object.
Plate fill: CTRL-R (add 2 edge loops), delete faces, fill gap (F)