I got a union to help connect up a whole house filter since the filter
has threaded inlets and it had some elbows nearby. I figured this
would make it possible to remove stuff later since I could unscrew
things without cutting all the pipe. The thing is, this stinking union
will not stop leaking at the compression spot. I've cranked it down
almost to the limits of what I'm capable of doing. Is this right? Is
it normal to crank the snot out of these things, or do I have a faulty
union or something?

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