I have a cake with the columns that are visible between 2 layers. How does that work with SPS? Is there a plate on the larger cake, then columns, then another plate, then the smaller cake? Or do I put really long columns that go into the larger cake, w/ no plate in between? Just a plate under the smaller cake.
What is the standard length of the pillars between the 2 layers?
Would it look weird to have a 2 tier cake, 6 & 9 inches, with the columns between? What about 2 tiers, 9 & 12 inches w/ columns betweeen?
Sorry, so many questions!!!
"Back in the day" nearly every cake had visible columns. SPS was developed "back in the day."
IMO, you use the multi-piece columns, using (1) 5" leg plus (1) 2" extender. That provides 3" of air space between the tiers. The cake should look bigger than the airspace IMO.
The bottom tier will have a plate and leg assembly in it as always, but the plate will be sticking up in the air, not resting on the top of the bottom tier.
Any of the sizes you proposed will look fine.