My wife needed a squaring up ruler for cutting quilt blocks and I thought I would have a go designing and printing one.

I've uploaded STL files for 6 and 7 inch (the largest that my printer can support) rulers, but the design can be customized in OpenSCAD to be as large or small as you need or to use metric measurements, if you live in a civilized part of the world.

By default, the ruler is pretty thick. It might work better to configure it to be thinner, but then you risk cutting into it when you cut your fabric.

I printed mine in PLA and was able to get good results using transparent filament for the body and then switching to black for the markings.

Anycubic

All-metal Mega

No

No

.3

100%

Use a high layer height and hot temperature to get the body as clear as possible. Mine was still quite cloudy, but is transparent enough when placed on top of fabric.