Brazing Stainless Steel

[SandShark]

Anyone ever do any oxygen/acetylene brazing on stainless steel using flux coated bronze brazing rod?

[2sac]

I don't know if you can get away with 45% but I've done it with 56%

[Olivero]

I've TIG welded using silica bronze rod but I don't think oxy/acetylene is a good option. I don't know that it preserves the chromium in the weld and so makes it not stainless anymore.

[ehsx]

Ss to cu. no capillary action, basically gas weld.

[ammoniadog]

A few years ago I dropped an old Revere pot and cracked it's rim. I smooshed it round again and brazed up the crack with 45% flux coated rod and it seemed to work just fine. I used extra flux, which I often like to do. Not sure if that makes any difference, but it seems like it does.

I'm a little surprised about what ehsx said above. Are you sure about that? I've done lots of silver brazing of copper pipe to steel Roto-lock valves and that has always worked just fine. Are you saying there's something about the stainless that makes it harder to join to copper than regular steel is?

[ehsx]

Harder to keep temperatures even. The bronze rods do not have capillary action, silver does.

Mfg wanted to eliminate silver to cut cost. Fluxed bronze would not work on flat face o-ring fittings and difficult on steel to cu except on horizontal surfaces. I was in charge of nation wide implementation, training and certification of brazers. Had to retain 45% silver for most steel/ copper & brass joints.

[ammoniadog]

Ahhh, we're talking about bronze brazing rods here. I misread. When I saw "flux coated", my brain instantly went to the blue or orange coated silver rods, since that's what I am used to. It helps that I'm not the one paying the bill for that stuff. I've never used bronze rods before. Carry on.

[2sac]

Ahhh, we're talking about bronze brazing rods here. I misread. When I saw "flux coated", my brain instantly went to the blue or orange coated silver rods, since that's what I am used to. It helps that I'm not the one paying the bill for that stuff. I've never used bronze rods before. Carry on.

As did I

[Red850kid]

I used silver brazing wire with some stay-silv to repair some helicores for someone's ice cream machine. The filler stuck well but I won't do it again. I had to use brasso to polish all of the scorch marks which took alot of time. But the joints started to discolor a bit days later like a greenish rainbow so I grinded them down a bit and used a rinsing solution which worked. I saved some money but it took alot of work to get the pieces looking like new again.

[SandShark]

Sorry for the confusion, but I was particularly interested in brazing with, what I've always called, "white rod". I've used it to braze steel many times, like Unistrut channel and simple things like that, but what I need to repair is stainless steel components for a commercial dishwasher. That's a whole different animal since it's food service. In case you're not aware, there are certain products used in food service commercial equipment repair specifically rated for food service.

Anyway, after doing some research on filler materials, the only brazing rod I've found rated for food service (Cadmium free) is a product from Muggy Weld called SSF-6. It can only be gotten from Muggy Weld and it's expensive.

Of course, I worry about damaging the stainless when heating it to over 1K degrees F, which might damage the stainless and cause it to rust, which I wouldn't want to happen since the components are inside the dishwasher.

I will probably have to take the components to a welding shop and have them TIG welded, which I was trying to avoid, but it looks like I have no choice.

Thanks for all the replies.

[Olivero]

Sandshark,

The chrome is the first to go when you weld stainless, if you cook it when Tigging, it'll rust. It's a delicate metal in that regard.

You could possibly weld it the way you want, but if you mix in bronze, there's no saying how that oxide layer is going to form over the stainless or if it even can with the bronze "in the way"

A small TIG machine and a small bottle of Argon is not that much money, you could make the investment and do it yourself, it's really not that hard.