Can I braze Stainless ?

[shaky]

I know I can silver solder it , but can I braze it in the same way that I gas braze mild steel?

[lh7018]

lh7018

stainless steel is chromium and nickel and iron I would sugest you look for a tradebrand inconel alloys these have simillar chemistry.

[shaky]

... as a filler rod I suppose
I want to make this in stainless rather than mild steel.

[hankj]

You can braze pretty much any metal with the proper filler rod and flux. You can also gas weld it.

Hank

[shaky]

So I needn't have bought the tig set

Is it just a stainless filler rod and oxy accetylene?

[joebass]

Silver braze, its done all the time in the restaurant industry.....http://www.jwharris.com/jwprod/hisilverbrazealloys/


I don't know about oxy acetylene welding SS. Pretty sure thats a waste of time, it will require the right flux and rod, a slightly carburizing flame, and it will not be as corrosion resistant as other welding methods. Also the heat input is higher so parts will warp.

[shaky]

Over here (blighty) we call it silver solder. I want to braze, to join stainless using brass as per the pic.

[Portable Welder]

Years ago I brazed a devider on a stainless sink and every thing was going good and all of a sudden it popped and the joint broke clean off the one side and I ruined a sink and my pride.
So I either tig weld it or use silver solder.

[Thomas Harris]

I know I can silver solder it , but can I braze it in the same way that I gas braze mild steel?

Most folks refer to silver soldering incorrectly, when in fact they are silver brazing. Soldering means low melting temperatures, usually around 400F or less. Brazing being anything higher than 400F, but not high enough to melt the base metals being joined. One thng about stainless is it's trickier to braze because of the oxides which can form. You need to find the correct flux and alloy. I think there is a site called HandyHarmon which gives extensive info on many braze and solder types/uses. Stainless needs to be fluxed and heated just right to braze properly. You also need to watch the joint tolerances closely too.

[dseman]

Over here (blighty) we call it silver solder. I want to braze, to join stainless using brass as per the pic.

Shaky,
Joe is giving you sound advice. He is referring you to fillers used for brazing SS. I believe you are misinterpreting what the term 'brazing' means. It does not necessarily mean soldering with brass instead of silver. Soldering and Brazing are both means of joining metals via a capillary bond. The difference lies in the temperature used to create the bond. Below 800F you are soldering, above, you are brazing. The choice of filler is based on which materials are being joined, and what conditions the final bond must satisfy. If you have a tig, it would be easier to use and would give you a higher probability of a 'first-try' success. Brazing SS is not like brazing mild steel. If you overheat SS you will lose it's corrosion resistance, and getting the filler to wet against the SS will require a special flux to remove the surface oxides. Silver is required as an alloying element in the brazing filler.

You haven't been very specific at all about your application. For all I can tell, your picture may be the leg of a table for a rabbit cage. In that case, the failure of the brazed fillet wouldn't hurt anything as the pipe would continue to support said structure. If this is your case, then you can use any filler you want. If you like the look of brass then try using the brazing filler you used for mild steel....good luck.

If however your picture displays something of greater consequence, you should really use sound materials and procedure. The following article will steer you in the right direction. While it is geared toward 304L SS, the same principles apply to other alloys:

http://brewingtechniques.com/library/backissues/issue2.6/palmer.html

-dseman

[Joe H]

Silver braze, its done all the time in the restaurant industry.....http://www.jwharris.com/jwprod/hisilverbrazealloys/


I don't know about oxy acetylene welding SS. Pretty sure thats a waste of time, it will require the right flux and rod, a slightly carburizing flame, and it will not be as corrosion resistant as other welding methods. Also the heat input is higher so parts will warp.

I have a buddy that gas welds SS all the time. He uses TIG filler rods, no flux at all. It works well for him. He does keep a rich flame, like you said, to make sure all of the oxygen is used.

[joebass]

I wouldn't trust those welds to be corrosion resistant or strong.

[Joe H]

They do fine for his purposes, which aren't safety critical.

I'm sorry, I accidentally told a fib about no flux! I forgot, he does use Solarflux to protect the back.

[shaky]

This is a great forum. Thanks for the diversity and detail of the replies.

The pic is the outer support for thr steering column on my dune buggy, It's kind of important!

My deliniation (in my head) has been that silver soldering is for teapots and necks on radiators, whereas brazing is for a strong joint on mild steel. I use it a lot on car body panels where it is difficult to access with MIG. It also looks a lot better.
Your temperature explanation helps me to understand the difference.

I know that brazing mild steel was used for constucting race car tubular steel frames. A local guy who did a lot of this type of work invented a piece of kit called a gas-fluxer which intoduced the flux into the gas flow.

From what you say here I guess it wouldn't be as strong when used on stainless (and the other problems) hence the tig welds which I am quite happy to do.

I was taught to weld in ths late '60's in the aircraft industry. There wasn't too much explanation of the processes, you must had to produce neat welds and the either passed or failed. We didn't seem to have too many crashed planes, perhaps I have forgotten them

thanks

shaky

[Thomas Harris]

[QUOTE=shaky]This is a great forum. Thanks for the diversity and detail of the replies.

The pic is the outer support for thr steering column on my dune buggy, It's kind of important!

Tig weld.