Well done - I especially love the hillbilly metal lathe action. . .lol.
I kept trying to figure out on how to make my own using a brass bolt or the regular barbed fittings (ones with threaded base) but didn't think of using the double barbed fitting, like you did - nice!
I actually have acess to a full metal lathe and milling machine, but with how little material you need to remove from the barb and the time to actually work the lathe, these little babies were done way quick. I had one done in the time it would take me to drive to my parent's house (where the lathe is).
Just take the thread die slow, you can twist off that end with too much pressure (I made that mistake once, but had bought an extra because I figured I'd probably screw one up).