First of all, I try not to. I think the stuff is horrible and prefer to not have it in my shed - however, sometimes you must (friend wants a repair; all there is in the hardware shop; other half doesn't want to paint the trellis she has asked for; bracket will be outside but hot-dip is too expensive...)
Even when you mechanically strip the coating off there always seems to be some that you miss, and don't get me started about the insides of galv tube.

Came across a galvaniser's association page Welding and around 3/4 of the way down they talk about brazing with GTAW (TIG to us backward types).
Key points are

  • Up the gas flow to around 12l per minute
  • tilt the torch over to 70 degrees



I tried it with welding and it did improve things. On normal settings, the arc would spit and contaminate the electrode as soon as look at it. With gas up to 12.5l (by the ball bearing gas gauge) from the usual 7 to 9 and slightly more angle, it seemed to push the zinc fume away from the torch and I even got a half way decent looking bead.
Still don't like the stuff but at least there is a hope that the electrode will last past the start of the arc.

I do wonder if this technique will work on brass, as I have some of that to do one day.

Michael

(and yes, I had a fan going to get the fume out of the area)


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