On Thu, 16 Apr 2015 10:50:03 -0700 (PDT), trader_4
wrote:


It matters when you have several fittings where they essentially
have to be done at the same time to assemble it. If the first one
sets up before you get to the last one, there won't be a last one.

You only glue one at a time. Put a pencil mark on the pipe and fitting
so you know EXACTLY where the pipe and fitting should be (do the pencil
mark when it's dry fit). You mentioned BLACK pipe, so if you cant see a
pencil mark, I'd probably use some whiteout.