Soldering copper pipe

Loves the Depot's copper bond

Not to beat a dead horse about wiping joints but I have a question... I'm not a pro, rather a plumbing enthusiast and I always like to learn. I was taught that when you sweat a joint, while it's still hot you take the flux brush and quickly swipe it around the joint. This flattens out the 'tit' and makes things nice and shiny. Then when everything is cool, I wipe the joint with soapy water and rag to clean the flux. In reading this thread, I just want to make sure I'm not confusing things... is using a flux brush to dress the joint different than 'wiping' the joint? And is what I do considered a good practice? Thanks!

My dad always wiped his joints when I was learning to solder. I decided to try it on one of my own joints after thinking I was ready to run with the big dogs. I grabbed a rag and after heating and soldering the joint, I used the rag to wipe the joint. What a mess, the rag was nylon. Hell, I didn't know about those kind of things. Anyhow, I can say that using nylon rags on how solder joints is not the approved method.

bob...

Yersmay using the flux brush to "smooth" out the solder joint while it is hot is the same as taking a rag and wiping the joint. As I posted from www.copper.org website it says sudden shock cooling and or wiping the joint is bad. Using a flux brush is considered shock cooling since, and you can be adding flux to the joint pushing out any molten solder. I just talked to one of the union instructors the other night. There is a ASTM standard for soldering pipes. ASTM B 828 and there is a test for this standard. In the test it says the joint is fail if to much solder was used, to much heat, and if the joint was wiped or shock cooled. So basically a proper solder joint is just the right amount of flux, heat and solder to fill the joint. After the solder joint is cooled they cut the joint in half long ways and peal apart the pipe from the fitting and inspected for any defects.

speedbump Heh, I made that mistake with a pair of gloves holding a pipe that was being soldered. All I can say is ouch. The union instructor also told me many plumbers come from the school of my dad, sponsor, or whom ever taught them did it this way. But it never makes it the right or proper way. I will admit when I first started into plumbing I learned to wipe away the tits and the joint while it was hot. But when I took the state test the state inspectors told me different.

We flick the tit with the solder being held in our hand and it falls right off.

(We are still talking about sweat soldering right¿)