On 08/18/2017 05:36 PM, Jim Wilkins wrote:
BTW auto-darkening helmets won't stay dark without the flicker of an
arc.

BS! In my lab I view induction-heated materials (boiling copper for
example) with my Northern Tool-purchased automatic welding hood. The
glow from white hot materials is about as steady as one could create.

Second example: A DCRP TIG welding arc does not flicker. Again a
steady and uniform glow.

Third example: I've used my hood to look at the sun. The first time
I held a welding filter in front of the hood just in case it wouldn't
get dense enough. It did.

John

John DeArmond
http://www.neon-john.com
http://www.tnduction.com
Tellico Plains, Occupied TN
See website for email address