Creating a cylinder with spiral loops, while preserving vertical loops

Question

I'm trying to recreate some geometry for a lighthouse model. A particular feature of this goal mesh is that it has spiral loops going around the cylindrical lighthouse. (ignoring the boolean cutout holes in this example)

I've tried a few different things, notably trying to use a screw modifer which causes the faces of the cylinder to loose flatness/smoothness. And I've tried using "poke, and convert to quads" to generate this shape. Both of these attempts cause the mesh to be less smooth, and looses the vertical loops.

How on earth might this shape be made? Hugely struggling to wrap my head around this mesh. Thank you for any suggestions!

Answer 1

Here is my technique, such as it is:

• Enable Add Curves: Extra Objects add-on in preference if you haven't already.
• Create an Archemedian Spiral and give it 3 turns and a height of 1. Set Steps to a value that will give you a reasonable smoothness. I selected 32.

• In Object mode, select the spiral, navigate to the Object->Convert submenu and select Mesh
• In Edit mode, select all and extrude along the Z axis until the extrusion just touches the existing curve:

• Select all and Merge by Distance
• Loop Cut and Slide to add 9 loop cuts. This will give you the 10 bands you want.
• It's easiest to add materials at this point. Add a new material. That will make the object that material. Add a second new material. Select every other band and apply the material to those bands.
• In Object mode, Shade Smooth

All that's left is to trim the top and bottom. Probably the easiest way to do this is with a knife project.

• In Object mode, add a plane.
• Rotate it 90 degrees on the X axis.
• scale it up on the X axis.
• Apply the scale and rotation.
• Move it -2 on the Y axis.
• Select the plane and then the spiral thing.
• In front view, enter Edit mode and select Mesh->Knife Project
• Make sure Cut Through is set
• Go to Vertex Select mode, invert the selection, and delete vertices.

For a final touch, in object mode, set origin to geometry and set the location to the origin.

Answer 2

You must be assigning the Screw modifier to an unsuitable original mesh? Half the point of using Screw, as opposed to twisting a cylinder, is that you can preserve the verticals, and wind up with near-planar quads.

Start with a simple vertical edge, away from its object origin on one axis..

You can even use further modifiers (Displace, or maybe Simple Deform > Taper) aimed at a Vertex Weight Proximity weighted vertex-group, to do the tapering for you...

..but you probably want to level the top and bottom of the spiral by hand, which means applying the Screw, anyway, so that would be too involved. Happy to help, though, if you want to go that way.

EDIT:

@Marty Fouts made a comment, while I was editing this answer: I agree with him, it would be much easier to do this with a little procedural shader, taking advantage of the default UV of a cylinder, unless you need the spiral in the geometry for brickwork, or somesuch:

Adjust the scale of the Wave texture to vary the number of turns. Adjust the Z-rotation in the Mapping node, tilting the stripes across the UV square, marrying them at the jump from U=1 to U=0, and you have a spiral.

That would save you quite a few chores, in modelling.