I decided I'd do a practice fillet braze with brass today. No plans on a fillet brazed frame in the works, but someday maybe. It went ok but not perfect. I have a question about it.

First off, I'm using oxy/acet. The brass I'm using is the cheap 5 pack of flux coated wire from The Home Depot. I'm practicing on steel cut out of a frame I built a little while ago that I'm using for scrap now (The frame didn't turn out good enough for my perfectionist mind). Anyway, I mitered it up and wiped it down with acetone (I didn't take the hydrochloric acid toilet cleaner to it, but it was pretty clean). I brazed it up and it looked as though the brass was melting in the joint nicely.

After it cooled, I took a file to it and tried to clean it up a bit. Not easy. I don't know how you guys get them looking so clean, but that's another post. After attempting to clean up the aesthetics a bit I did a strength test. I put almost all my weight on it and the metal finally kinked near the joint but the tubes stuck together. I'm guessing that is a good thing. I then continued to mess with it until I got the tubes apart. There were only a couple small spots where the braze had flowed inside the tube. When I was brazing I was getting the tubes pretty darn red. They were hot but since I was just practicing I wasn't too concerned about it because I just wanted to get a good flow with the brass. I don't understand why the brass didn't flow well even though the metal was so hot. How do you get it to flow if the metal is already too hot? Is it the cheap brass I was using? Not enough flux on the rod to adequately allow the metal to flow? Should I get some better quality brass (not flux coated) and a tub of flux to practice with? Although it was a strong joint, I certainly am not ready to be fillet brazing frames quite yet. Any suggestions are appreciated. Have a nice weekend everybody!