the upholstery type 'cardboard' is about 3x the thickness of the usual boxboard, but less than corrugated - here's a currently available type, better quality than the 50's era stuff, and than the repro panels in my experience

Bill


Moved over to the Passing Lane

"When we tug a single thing in nature, we find it attached to the rest of the world" ~ John Muir
"When we tug a single thing on an old truck, we find it falls off" ~ me
Some TF series details & TF heater pics