Sorry stuart, but I MUST disagree with you - vehemently. I don't know if you own, or have ever used an electric "file"? I have and own a B&D example. It does have its uses, but "filing" is NOT one of them - NOT if you want any degree of accuracy and a smooth surface free of scratches that is. In short, that tool is absolutely "mis-named"! The "real ones" are mainly used in places like car body shops.
Brass is NOT all that hard (depends what you compare it with I guess) but as COWS clearly wants a smooth "high class" finish I can assure you from personal experience that it's MUCH easier to put a scratch/es into brass, but VERY VERY much harder to take it/them out again!
The "only" way to get the sort of finish on brass that COWS wants - after hack sawing to approx profile - is to use a smooth hand file, paying especial attention to clearing swarf from the file after every few strokes. Then finish off with VERY smooth wet & dry - 600 and higher - on a sanding block. Then polish on a buffing wheel lightly loaded with compound.
The buffing wheel is the ONLY power tool needed - OR which should be considered IME. (And BTW, that can be a simple cotton mop wheel, if necessary held in a power drill on a stand if no proper buffing wheel is available).
But "electric file"? Nah, sorry.
As I said in a previous post on this thread, about 15 mins work - MAX. But let's double that because it seems that COWS has little experience of using hack saws and files, so needs a bit of practice first. But he does already have the necessary "skill of hand" as his "wood workmanship" clearly shows in the pic he posted up above somewhere.
