Been having a nightmare of leaks trying to get some new galvanized pipe in a wall for a bathroom sink.
Started out using plumber's pipe dope in a tube on both male and female portions of pipe threads, but it had several small leaks.
When I switched to the Teflon tape the leaks stopped.
The old pipes had the dope on them and they came apart pretty easily in the old 60 year old house, so I used the dope again but the thing seems to leak more with it than tape. True?