The solder doesn't take (start flowing, leave the iron) when I use my copper soldering iron. worked fine before.?
I tried filing it, it is mostly flat. I see solder has attached to the sides, I do not know how to remove it. The solder on the iron looks wonderful, like I was taught it should look. I played with the temperature, no success. The solder will not take. I would appreciate any information you have to share with me. I am a new metalworker and solderer and have run out of troubleshooting advice that I was taught. My tip is about 1 cm by 5 or 6 cm.