https://qrcode2stl.printer.tools

use this link to generate qr code or some other similar website.

IF the hexagons don't fit properly, it's most likely due to thermal expansion or thicker/thinner walls. Just resize by 0.5 percent and reprint and it will fit properly

The model is suited for 100mmx100mm square width depth of 6mm (but depth is less important) so just scale it by your_side_length/100. I made it for my moms hair salon so scan it and rate 5 stars if you have the time :))