The Origami Forum

As many people who have done a poor job of trimming a rectangle to a square will tell you, folding a model intended for square paper from a sheet that is slightly rectangular or trapezoidal can be a royal pain, which got me wondering: how good are the tolerances of A-series and B-series paper sizes?

I know that A-series and B-series paper sizes are rational approximations of sqrt2:1 rectangles to the nearest millimeter, and while I'm sure this is good enough for scaling printed materials, is it good enough for origami? Can a model designed for A4 paper be folded without much trouble from other A-series and B-series sizes? Assuming an accurate cut, would removing a largest square from a sheet of A-series or B-series paper produce a blank suitable for models that call for 1+sqrt2:1 rectangles regardless of which size you start with?

I am certainly not an expert on European sizing standards, but I recall that some sort of rational number was chosen for the lengths and widths ( you can't calibrate to an irrational number). A quick Google search shows 210 mm × 297 mm for A4. More importantly, I would think there is a big difference in quality from manufacturer to manufacturer (there certainly is for papers here in the USA). As many dollar bill folders cram geometries in their models that really are not a perfect fit, I would imagine that any A-sized producer should yield a much better folding experience. - Marc