Protective Gas

ABI and Puk pulse arc welders can use pure argon gas as the
protective gas when welding.

But I hear that you can add 2-5% hydrogen to the argon gas to give a
more reducing atmosphere for welding silver and gold, which would
seem like a good idea.

Any experience about this from fellow Orchidians?

In my experience as an Engineer in the industrial gas industry with
the gases and in pursuit of super quality stainless steel Tig
welding we did not find any real reason to add hydrogen to argon. We
did try it but found that with good argon and proper pre and post
weld purging we got no improvement will hydrogen addition. A
competitor did claim advantages but we found none over our normal
high quality practice.

Welds were examined visually and sectional samples inspected by
scanning electron microscope at 3500 magnification. I don’t believe
you would see anything different with pulse welds on gold and
silver.

jesse

In theory, this makes sense, but in practice with smaller arc welders
it does not since it is very difficult to correctly maintain a small
percentage (2-5%) with bottled, regulated gases. It is far easier
less complex, therefore more likely to produce uniform results using
only one gas such as argon. I believe it was an Orchid contributor
who once wrote or quoted “In theory, there is no difference between
theory and practice. In practice, there is.” Due to the equipment we
sell, I have a great deal of on using inert gases, and
balancing gases for torch work if you would like to contact me off
line or give me a call.

Best Regards,
Gary
Gary W. Miller
Sr. Technical Advisor
www.spirig.com