howdy
i was where you were last year. come to think of it, i'm still there! nuts. well, got a kid in college and one more going in a year, so .... it's just nice first world problems to have.
when i asked your question last year, it generated this thread:
http://www.bikeforums.net/framebuild...costs-ugh.html
it's loaded with massive amounts of great info from Doug and others here on the boards.
and this recent helpful regulator thread:
http://www.bikeforums.net/framebuild...r-s-setup.html
final comments that you probably should NOT follow:
- if you find yourself completely unable to keep a torch away from a bike frame, and you don't have the cash to build bikes, you might get the idea to do something like buy a cheap frame set on CraigsList, then torch-r it into something slight different (hopefully better).
i picked up a beat up Nishiki for $25 and added DT braze-ons, rack bosses, second set of bottle BOs. You can see it
HERE.
I would recommend you heed the advice from the experts and don't do this. Although I've had a good time doing it, and the lower costs keep my marriage together!
If you do all the reading, you'll find the cheapest option that lets you do anything is a MAPP gas torch from the hardware store. It'll flow silver, but not brass/bronze. Sil-brazing is OK for a things like bottle cages, shifter bosses. Probably OK for rack bosses, but if I could do bronze, I'd go that way. Definitely NOT brake bosses. And MAPP/air will never give enough heat for a safe lug, I think.
That's my two cents. Worth at least half of it.
Cheers!