OK, more research I should have done years ago. Most people who have these irons know that the tip temperature is controlled by a reed switch turning the heating element on & off as it reacts to a thermo-magnetic slug in the back of the tip and we should all know that the number stamped in the slug is the operating temperature in hundreds of degrees F.
I never noticed before that Weller doesn't recommend the use of tips above 700 degrees except when absolutely necessary and specifically says that hotter ones won't last as long. (That could explain why the genuine Weller PTB9 tips I've been using fail so soon).
I also took a few minutes to extract this chart from the manual for reference while I'm shopping for tips.
