Why do you need to make one?
I use these guys for all my specialty hose work.
I don't know if you can order what you need through them or if you might have something similar near you.
"But it does me no injury for my neighbour to say there are twenty gods, or no god. It neither picks my pocket nor breaks my leg." - Thomas Jefferson, Notes on the State of Virginia, 1782
Arguing with a truck driver is like wrestling with a pig in mud, eventually you realize the pig enjoys it.