Framebuilders - Black and white Stay-Silv?

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rodar y rodar
08-14-09, 05:31 AM
I know it`s generally suggested to use black for stainless and white for other steels, but are there any bad effects from using them otherwise? I bought a single jar of the white flavor about a year ago and was using it for all my silver brazing. That jar seems to have been kidnapped by aliens or something, so I need a new jar and thought maybe the black would be better for an all purpose silver flux. I guess I could buy both, but besides spending the extra few bucks I kind of prefer to keep things simple. If it makes any difference, I`ve been using it with 45% Cad-Free (AWS A5.8BAg-5), mostly on shop tools (tap and drill extensions), anything too tiny to TIG or bronze braze, and some occasional bike parts (stradle yokes, accessory bosses). Harris`s site does specifically mention stainless for the black stuff, but it doesn`t say NOT to use it for cromo or plain old cold roll. Their description of the white stuff could also go both ways the way I see it. So, should I expect any new problems using the black for all purpose? Keep with the white? Stop making a big issue out of something that isn`t really that important in the first place?
unterhausen
08-14-09, 04:15 PM
seems like I saw something that said the black isn't clear when hot. I need to go get some for stainless, I see nothing wrong with it as a general purpose flux. I've seen people say that the white stuff works fine for stainless as well if you have good heat control.
I use the white for stainless and I can't say it is due to my superior heat control. I mostly use it for attaching small bits of stainless to chormo, if that is a difference. I am not sure I have used it SS to SS. I have a small bottle cage I was planing to do just that with when I get back in the shop. Didn't know it was wrong.
rodar y rodar
08-14-09, 09:35 PM
Thanks. I was probably making a big deal out of nothing- I posted in the wee hours of the morning with nothing going on and still a couple hours left before I could go home and go to bed, so prime environment for an overactive imagination. If I had managed to find my flux, I could have been busily working away on my new mountainbike rack instead of inventing problems :)
Live Wire
08-14-09, 10:38 PM
Black flux will work for any silver brazing you'd want to do on a bike. Because it can go to a slightly higher temp than the white, I like to use for doing things that will take more prolonged heating. Like brazing stainless faces on dropouts.
Like unterhausen said, the only real drawback it that it makes things harder to see while brazing- it will turn clear only where your are brazing at the time, the rest turns back to black so it's hard to check your work when you're done.