I was working with an apprentice today and he began to dope the threads on a union. I thought he was joking and I started laughing, and he looked puzzled. He said that he had been taught to dope the threads. Have I missed something? I have been in the trade for 16 years and have never put any kind of thread sealant on union threads.
Please find me a place where I can find something in print to debunk this notion that you need dope on union threads.