Many of the foundationless frames That I have seen pictures of get drawn out to the sides and the bottom but not touching. If you glued a Popsicle stick in the center of the sides and the bottom will the bees attach the comb sooner so you could eliminate the need for the wires?
Perhaps, but why waste the effort, wiring is a lot easier.
How long would it take for this to happen?
months, years, never....... All depends on the hive and location. The weather in the south permit bees to build more comb than in the north.
I have some, that never get drawn to the sides or bottom. The one shown in my initial post is about 3 years old. As the comb gets older, there is less and less chance that the bees will add to it.