The pvc/cardboard/acrylic ... tube.
Determining length of the tube for arbitrary diameter.
Single primary winding.
Red, angle between criss crossing. Green, angle between next winding of same primary.
Angle between different primaries.
Fast animation of windings.
Slow animation of 12 windings per primary.
The completed primaries.
A template that can be printed to ease the process of marking the grooves.