What do you do when you have a bunch of 1" Kee pipe fittings but per code handrail requires 1-1/4" pipe?
I like the look of the smaller 1" fittings with the 1-1/4" pipe for handrails, they are a lot more finished looking, IMO. Needed to build 6 sections of handrail to complement the "Mountain Industrial" look my bride envisions for this place- 2 for the inside stairs to the loft and 2 each for the front and back decks.
In order to make them work, I just sleeve the larger pipe with either 1" pipe or a 3/4" coupling. Either one is a fairly close fit with S40 pipe and works great with the Kee fittings. Used few couplings this time; they came out of the discard barrel next to the pipe rack at the local plumbing supply house.
I like to plug weld the sleeves in place, it gives me a nice square end cut to **** the fittings against without a weld to contend with.
Once I figure out the length, first step is to drill (3) 5/16" holes at roughly 120° apart.

Stick-out is about 1-1/8" to avoid interference at 90°. A quick tack weld in one of the holes allows me to tap the sleeve to center and square it up with the railing.
A nice hot rosette weld follows, only takes a few seconds to fill the hole. I really like to burn these welds in hot.
A quick pass with the M12 grinder and a 40 grit flap wheel takes off the protruding weld bead.
The smaller fittings snug up nice and tight against the larger pipe. (The set screws are installed on the bottom side during final installation)
I'll sand all the welds all flush with 80 and 120 grit belts on my 1.5 x 30" pipe and tube sander before handing them over to the powdercoater.
More to come.