My new Moen shower valves have female threaded ports. I am sweating male adapters to my pipes and then connecting to the valves. I then have further sweat connections between valves and to the supply lines and shower heads. I won't be able to really test for water tightness until the system is complete, but by then I won't be able to disassemble the threaded connections. How can I tell if they are correctly tightened? Is it possible to overtighten? The connections are rigid copper to brass, 3/4", no compression. I'm using tape on the threads.