Classic #IonicCapital #Tectonic Surfaces Plan

We already made the 8 unit tall #fillet at the bottom of the #capital a part of the #shaft in https://pixelfed.social/p/Splines/791794072490907090. So, excluding that, the remainder of the capital is 14 parts or 112 units tall, for the bottom half of which we use the #revolve operation (like the #columnBase and #columnShaft), and for the top half we use the #extrude operation (like the #pedestal, #entablature, and #plinth).

Starting at the bottom, we have an #astragal that is 2 parts or 16 units tall and has the same profile as a #reed and #torus, falling in between the two in terms of size. The arc AD is shown in gray because it is an invisible #virtualSurface that envelops the decorations like #eggsAndDarts on the #ovolo. This is the measurement that is given in #Scarlata's #PracticalArchitecture, but it makes no mention of the #decorative and #tectonic surfaces. Arc BC with a radius of 4 parts or 32 units is the tectonic surface on which the Ovolo decorations rest. Such decorations have a variable or uneven surface which may not exceed 1 part or 8 units.

Points E and F mark the horizontal tangent or maxima of the second spiral and the first (outermost) spiral, respectively. The gap between them is exactly 4 parts or 32 units. GH is the profile for the vertical side surface on which part of the #ribbon and #braid lie flat, protruding exactly 6 units to coincide with the invisible virtual flat surface through EF.

The #cymaReversa is 2 parts or 16 units tall and 1.5 parts or 12 units wide. It starts 4 units to the right of F and stops 4 units short of the top fillet, which is one part or 8 units tall and 20 parts or 160 units from the #columnAxis.

Of the 4 parts or 32 units between G and H, the lower 3 parts or 24 units are part of the #voluteChannel groove and the top 1 part or 8 units is a fillet that follows the curve of the #volute and progressively gets narrower until it converges with the #eye of the volute.

#IonicColumn #VignolaBase and #AtticBase #CAD Plans

Both #Vignola base and #Attic base have the same square footprint of 400 units x 400 units. The #plinth for both is 48 units (6 parts, or µ/3) tall, and the total height for both is 144 units (18 parts, or exactly µ). As such, they are easily interchangeable.

In the Vignola variant, we start at the plinth with a #fillet 2 units tall and a classic #scotia 18 units tall gouging out part of the fillet.

Then there is another fillet 2 units tall, followed by two #reeds, each 8 units tall, followed by another classic scotia as described above.

This is followed by yet another fillet 2 units tall and topped off with a #torus 40 units tall. A Torus is the same as a reed, except larger. When we reach the neck of the shaft, we will see another molding called #Astragal which has the same profile as reed and torus, but sits in the middle in size. Think of reed, astragal, and torus as small, medium, and large of the same profile.

The modern Attic variant is more elegant with fewer moldings. It also gives the impression of more heft for more stately columns. It starts at the plinth with a torus 36 units tall, followed by a fillet 4 units tall, followed by a modern scotia 24 units tall, followed by another fillet 4 units tall, and topped off with another torus 28 units tall.

As in the construction of #IonicEntablature [https://pixelfed.social/p/Splines/791013152244518907], split the construction of the #columnBase into two steps.

Just as we extruded #dentils separately, we extrude the plinth separately. First draw a square 400x400 in the top view. Then extrude the square 48 units in the front view.

For the rest of the base, we need a new 3D operation — #revolve around an axis. Instead of extruding the #primaryProfileCurve, we revolve it around the #columnAxis, and cap the #planarHoles on both ends before performing a #booleanUnion with the plinth. Finally check edges of the solid for #nakedEdges and #nonManifoldEdges.

The #column is the most complex component — not least because of the beautiful #capital at the top. It also offers the most opportunities for creative expression, as long as designers differentiate in the #decorativeElements, not #tectonicElements.

There are 3 subcomponents of a column — the #columnBase, #columnShaft, and #columnCapital. In the #IonicOrder, there are variants for each of these components, not just in the tectonic portions, but also in the decorative portions, and it is equally acceptable to mix and match them.

Classic variant of the column #base bears #Vignola's signature in a new #molding called #scotia. There's a "modern" version that has a newer Scotia. I am trying hard to resist the urge to call it #NovaScotia.

The column #shaft is not perfectly cylindrical. It gradually tapers off in the upper 2/3, has a plain unadorned variant, and a #fluted variant.

Classic variant of the column #capital has parallel flat #volute slabs only visible from the front and back, but not from the sides. There's also a modern variant that has curved volute faces on all four sides with pointed ends at all corners and optimized for use in a corner column, but not limited to that.

These variants can be freely intermixed in any combination of base, shaft, and capital. The sketch shows an Ionic column with a modern base, fluted shaft, and classic capital, but any other combination would be equally acceptable as long as all are internally consistent in a single #colonnade or #arcade.

Beyond these tectonic elements, there are decorative elements like the #eggsAndDarts motif in the #ovolo of the capital. The eggs can be convex or concave, the eggs and arrows can look different, or the Ovolo could have a completely different motif, or none at all.

The bell-shaped #scrolls between volute slabs are separated by a ribbon or belt with a 3-strand braid not seen in this sketch. If you design fashion accessories, experiment with other designs while maintaining proportions.