Tig welding brass

I have AC/DC tig with argon.
Can I weld Brass with it?
Do I use AC or DC ?
Can I use brazing rod as filler?
Cheers guys for any info.
Reply to
Triker
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I think the most common way is to BRAZE IT!
Triker wrote:
Reply to
Al Patrick
I don't want to use a gas flame and flux. I want to weld it with the tig.
Reply to
Triker
I tried this myself at school last week with no success. Then my welding instructor came into my booth and asked me what I was doing. "Trying to tig weld brass.", I replied. "Can't be done.", he said. So with his knowledge and my direct experience, I would say it can't be done...
The problem is that the zinc bubbles out in ugly little blisters, sort of poison ivy looking nastiness. I have decided to use mechanical fasteners - picked up brass hardware at Home Depot for 88 cents...
Of course, I might be wrong...
Reply to
Emmo
Yes, you can TIG weld brass. Use RCuSi filler and DCEN. Be aware that the zinc will fume. You don't want to breath it because the fumes will make you sick as a dog. And it will likely cause some porosity in the weld metal. Keep the arc on the filler metal to avoid burning the base metal. Use stringer beads, don't oscillate.
Reply to
Footy
You can TIG Braze-weld it using silicon bronze or sil-phos-bronze filler, but keep your heat very low or you wil burn the zinc out of the brass. Besides giving off toxic zinc oxide, burning the zinc out will also change the color, making it redder.
The sil-phos melts a little lower so you tend to burn less zinc.
Color match will be OK if polished, and coated. If the surface oxidizes at all, the weld will show up bright as day.
Reply to
Ernie Leimkuhler
I have AC or DC. I can not reverse the DC electrode current. So do I use AC?
Can I use normal brass as the filler rod?
Reply to
Triker
I tried normal bronse filler rod, using DC tig. The whole thing cought and spluttered and covered everything in light coloured powdery soot. I guess I did something wrong, yes? What?
Reply to
Triker
Wrong filler. You are trying to use Low-Fuming Bronze for gas brazing. You need Silicon Bronze or sil-phos bronze.,
Reply to
Ernie Leimkuhler
Cheers Enrie, I thought it was the filler that was making it all flair up. Was I right to use DC?
Reply to
Triker
The zinc in the brass filler will fume and caused increased porosity. You can try it. But you will be better off using the silicon bronze recommended previously. And if you are already having trouble with fuming, I don't think you will like the results with brass filler.
You want to use DCEN to put most of the heat on the work because of the thermal conductivity of coppper based alloys. You could use AC. But you will have to use a larger tungsten and higher current.
BTW if what you are welding is much more than about 1/16" thick, you may need to use an argon-helium mix to get adequate penetration and weld pool control.
Reply to
Footy
No. Brass is an alloy of copper and zinc, and zinc has an infamously low boiling point . If you heat brass to anything like the temperature of a TIG torch, you'll lose an awful lot of the zinc as fumes or zinc oxide. Find some silver solder and a cheap low-temperature gas torch and do it that way instead.
There are also questions as to what brass alloy you're using. Some are easier to work with than others.
(I know this is really sublimation not boiling, but you get the point)
Reply to
Andy Dingley
AC works, but DCEN works better.
Reply to
Ernie Leimkuhler
I can set my tig to AC and get 80/20 percent either way. It also had the normal CD for normal CD tig welding... is this DCEN?
Does "DCEN" mean direct current electrode nutral?
Reply to
Triker
Direct Current Electrode NEGATIVE
Triker wrote:
Reply to
Al Patrick
So that should mean that the spark jumps from the brass to the tungsten, yes?
Reply to
Triker
UH...electrons are negatively charged...in this universe. If you have positively charged electrons (called positrons or antimatter), then you come from a parallel universe and must have a goatee.
DCEN means the current goes from the tungsten to the base metal.
Reply to
Ernie Leimkuhler
A long time ago it was commonly thought that electric current flows from "positive +" to "negative -". However, in more recent years it has been proved that electric current actually flows from "negative -" to "positive +" .
It actually flows in the opposite direction to what is shown on a circuit diagram.
Reply to
Triker
Regardless of how you view current, DCEN means the electrons flow from the electrode to the work, and positive ions flow toward the electrode. Considerable energy is required to make the electrons leave the electrode. This is called the work function. When the electrons hit the work, they give up this energy. What you wind up with is about 70% of the heat on the work and 30% on the electrode. This is what you want when welding copper based alloys.
If you use AC, about half of the heat will be on the work, and half on the electrode.
FWIW both views of current are still in use.
Reply to
Footy
*However* only one view refers to metal current flow. The other is semi-conductor hole flow.
I believe even the electrical trades have long given up + flow they got from Ben Franklin IIRC.
Electricity and Electronics is electron flow that is e- flows to the +. Solid state Electronics inside a crystal allows hole or e+ flow.
We are talking about welding rods and Tig - so the electron e- is king.
Martin
Reply to
Martin H. Eastburn

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