By the way, boric acid (in a powder form) is available at almost
any pharmacy, in the eye care section. Took me a while to figure
that one out!
A 50%/50% solution of boric acid and alcohol works well for
firescale prevention. Ignite the alcohol after dipping the piece
and as it burns off it leaves a coating of the boric acid. Flux
your joints and pickle after soldering and your on your way.