From the “what have I learned in life” collection, from trying to learn various trades as a challenge…
What is the difference between metal tubing and metal pipe? They are both round and have holes through them, but there is a big difference. Tubing is measured/specified by outside diameter, since it is intended to be used in structural applications. Pipe is measured/specified by inside diameter, since it is intended to carry gas/liquid inside it.
With that said, furniture-grade 1" PVC pipe is actually 1.315" outside diameter, which will be a snug fit if you just put the Sky’s pole mount over the pipe without a cap…