YEA .
The PAPER can expand / contract maybe 3/4 inch to a A1 sheet , from humid cool to schorching dry . so like horsepower , needs a Std. barometer Correction .
Eres Mr Fanchers contribution .
Four Ninty and Fourty eight , are almost the same , bar a decimal place or two .So an inch is ten . More or Less . So four inches is fourty , twice is eighty . But if its eight its thirty two . Twice .
Ahem , if the CHORD of the ribbed bits EIGHT , ya getta bout 30 a side , so a extra 60 or 65 or so . thereabouts . Which is about 10 % more area . or , at the same weight , 10 % less loading .
Or can Go Harder , before you load it up to the Std. limit .