Shower Valve Body Installation (NPT)

This seems like such a simple problem, but I'm at a loss as to how to deal with it.

My wife just purchased a Jado shower head and valve body (pressure balanced). The inlets and outlet are 1/2" NPT. How the heck do I thread the copper supply pipes onto this? The supply line is always going to be immovable.

The supply lines are fixes in place, so they can't turn. If I thread-on an adapter and then solder to the copper pipes, how do I know if I've gotten the adapter tight enough? I'd have to turn the water on to find out, and by then it's too late.

What am I missing? This seems like such a simple issue, given that a lot of valve bodies come with this type of hookup.

-Hans

Solder pipe to adapter
mount faucet
install adapters w/pipe to faucet
then pipe to faucet.

Thanks. I had done a search here, but my search terms were too vague and I got too much info. A search on the internet yielded a few clues that agree with what you listed.

I suppose the key is knowing how tight to make the connections to the valve body, and making sure to use pipe compound.

For thread sealant, I like something like rectorseal with Teflon paste.
The trouble with tape is that heating the pipe a ways a way can affect it.
When threading a MA into a valve, I crank it in pretty darn good.

can't you also slip 1/2" copper into the shower valve and just solder it on there?

i know the kohler ones work like that. you can either use the npt or solder.

For some reason, Jado builds their faucets to NOT allow the soldering on the inlets and outlets. You can't fit the 1/2" inside and it specifically says not to try it.

The quality of the threaded fittings these days is often pretty crappy. It might be worth paying the extra for a brass one if you can find one with nice clean threads.

I'll look for brass. Any issues with soldering copper to brass? I've done it before, just not sure if i've done it right

Copper solders just fine to brass...