That old plumber on the job in Canyon really set me straight about flux.

I was sweating some copper lines in a 1970s house near Wolflin and the guy just watched me for a minute. He finally said, 'Kid, you're using that brush-on paste like it's free. You're leaving a mess that'll eat the pipe in a year.' I was just globbing it on. Now I use a tiny acid brush, apply a thin, even coat, and wipe off any excess with a rag before I heat. My joints are cleaner and I don't worry about pinholes. Anyone else get called out on a bad habit that stuck with you?

3 comments

3 Comments

max2232mo ago

Wait, you were just brushing flux on without wiping it off first? That's wild. I can practically hear the corrosion starting. A thin coat is the whole point, it's not glue. That old timer saved you a ton of callbacks for leaks. Good on you for actually listening to him.

ray_williams2mo ago

Yeah, "thin coat" was a concept my first joints clearly never got the memo on. I was basically building solder dams.

logan_mitchell2mo ago

Remember to wipe the brush on the can's edge first.