I know this can be a lot of different sizes, but what is a good length to cut the various pipes for about a 24"x24" version that the bundled parts will build. This includes the lengths for short pipes on the Z-axis.
I bought 2 - 3/4"x10’ pipes from Home Depot. The 3/4" pipes at the Lowes near me seemed to be closer to a .88" O.D. They were also 30 cents less expensive at Home Depot for each pipe.