I used a wood/string mat (think heavy gauge sushi mat) on a 3 seat sofa 25+ years ago with excellent results.
The product linked was simply to show the concept.
Currently I would probably try corrugated plastic or plastic-cardboard sheeting for starters and/or the closely spaced cloth connected thin wooden slats supplied with cheap beds/mattresses.
You could also experiment with heavy duty corrugated paper from shipping containers.
Something supportive, but somewhat compliant is the ticket, IMO.
I worked for Kneedler-Fauchere for over a decade in the 80's/90's and part of my duties involved writing showroom tutorials for their "custom" furniture vender lines.
DeKay
The product linked was simply to show the concept.
Currently I would probably try corrugated plastic or plastic-cardboard sheeting for starters and/or the closely spaced cloth connected thin wooden slats supplied with cheap beds/mattresses.
You could also experiment with heavy duty corrugated paper from shipping containers.
Something supportive, but somewhat compliant is the ticket, IMO.
I worked for Kneedler-Fauchere for over a decade in the 80's/90's and part of my duties involved writing showroom tutorials for their "custom" furniture vender lines.
DeKay