Which brass alloy?

Education Welding
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Hi people, newb here and looking to solve some mysteries of my own :slight_smile:

So, I am getting into framebuilding and slowly gathering materials/tools to build my very first frameset. Since I’m trying to source most of the stuff locally, I came across these brass brazing alloys the could (but not totally sure) work well for some fillet practicing, and I wanted to ask here if they are indeed adequate for the job.

So far I have:

RBCuZn-A with chemical composition Cu: 59% Si: <0.3% Sn: <1% Zn: rest

CuZn40Si with chemical composition Cu: 59,5–61,0% Pb: <0,02% Fe: <0,25% Ni: <0,10% Sn: <0,20% Si: 0,2–0,4% Al: <0,01% Zn: rest

Thanks a mil to everyone,

Tudor

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The high Si content of that stuff makes me think it is for TIG-brazing. Is that what you’re doing?

For flame brazing (oxy-acetylene or oxy-propane usually), you’ll want the RBCuZn-”X” where X means some letter. I don’t know what the final letter means, but I always use RBCuZn-B or RBCuZn-C. Typcally called “Low-Fuming Bronze” or LFB. (Brass and bronze in this context mean the same thing)

It might help us if you tell us what “locally” means. Where ya from?

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Hei bulgie, I’ll be doing oxy-peopane brazing. I’m based in Romania but have no problem ordering from the rest of EU, just wanted to avoid the bigger shipping costs (if possible), and help the local economy :slight_smile:

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RBCuZn-A Naval Bronze (RBCuZn-A) is a copper-zinc brazing filler metal containing small amounts of tin to improve strength and corrosion resistance in the weld deposit. It is a good choice when the high strength properties of low fuming bronze are not required. A borax-boric acid flux is generally required when brazing with this product.

Tensile strength kpsi: 50

Wonder if some frame builders have used this over the years

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Hei bulgie, I’ll be doing oxy-peopane brazing. I’m based in Romania but have no problem ordering from the rest of EU, just wanted to avoid the bigger shipping costs (if possible), and help the local economy :slightly_smiling_face:

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Cool! Glad to have you on the forum. Keep us posted on your progress.

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Thanks bulgie, appreciate it!

While digging some more, I’ve found some RBCuZn-C rods but flux coated. Shouldn’t be a big deal removing the flux through soaking in hot water. I’ll start here and see how it goes.

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Last time I needed to take flux coating off (in the ‘70s!) I hammered it off, just takes a few seconds. Maybe wear a dust mask, the dust probably isn’t toxic but it can be an irritant.

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