Back to welding...

[280plus]

When you guys who use ox/acet to weld steel how do you set up your flame? Short sharp inner cone or a longer quieter flame? Assuming it's a blue flame that is.

[charby]

I like my blue flame to look like a Sapphire glowing on the end of the stick when welding mild steel. not too loud (too much oxygen) but not too long. Almost where it hurts to look at the flame with out shaded goggles.

Brazing I like a little bit longer/dirtier flame.

[280plus]

Yup, I know the flame you mean. I want to try it, never have. I hear coathanger makes excellent filler. 

Why the dirty flame? I use a turbo torch with a big fat tip to braze so it's pretty clean. Are we talking yellow?

I was using my buddy's ox/cet to braze friday and I managed to pop a hole in the tube without even trying. Hadn't done that in years. So I started busting his chops and calling it his "laser" torch. 

[zxcvbob]

I use a neutral flame.  Start with it too rich, then slowly turn up the oxygen until the light blue middle cone just disappears.  (describing it from memory; I haven't done it in a couple of years)

[charby]

Why the dirty flame? I use a turbo torch with a big fat tip to braze so it's pretty clean. Are we talking yellow?

yes yellow, not sooty yellow, like you would use for annealing aluminum.

[PTK]

Welding should be done with a neutral flame.

[KD5NRH]

Just pile the coal up well right over the tuyere, and keep the airflow strong until...oh, wait, gas welding...nevermind.

[280plus]

Neutral meaning ox turned up until the blue cone just disappears? Like I would to solder.

Now, as far as a yellow sooty flame. IIRC this is a "Carburizing" flame.

http://en.wikipedia.org/wiki/Carburizing

Why do you use this for brazing? Which to me is high temp solder.

[charby]

Neutral meaning ox turned up until the blue cone just disappears? Like I would to solder.

Now, as far as a yellow sooty flame. IIRC this is a "Carburizing" flame.

http://en.wikipedia.org/wiki/Carburizing

Why do you use this for brazing? Which to me is high temp solder.

Just how I was taught, brass to steel brazing. Flame was sootless but more yellow than a nuetral flame.

[zxcvbob]

Wen brazing, you don't need as intense heat as welding, and the reducing flame (a.k.a. carburizing flame) acts as a flux to remove oxides.

[280plus]

Ah, I've never tried brass to steel. (I don't think anyways) Only brass to copper and copper to copper. Interesting thanks!