wasnt sure where to put this. i made a cheap and simple tool for flaring my heater pipes on my build. several people commented on it and to buy the tool that does the same thing is kind of expensive. you can make it pretty much any size you want, you just need a ball bearing thats roughly the size of the bead you want on the pipe, a piece of steel the same as the ID of the tubing youre flaring, a bolt long enough to cut a ramp in. i happened to make mine with a banjo bolt cause it fit in the pipe im using and already had holes in it, i just had to make them a bit bigger.
slide the ramp bolt all the way into the large bolt until the bearing sits flush
tighten the nut on the ramp bolt to force the ball bearing out of the large bolt while turing the large bolt inside the pipe.
to get it out just loosen the ramp-bolt nut and tap it back into the pipe. bearing pops back into the large bolt and it slides out.
so far ive used it on copper, steel and aluminum. works the same on all.