folding ruler 2m magnetic hinges

Everyone has one, like pens they vanish into some parallel dimension, they do break if you really need them.

A foldinge ruler 2m to measure furniture, rooms or makes.

This model provides insets for 10x2.5mm round magnets as hinges and 6x2mm magnets for stability and snap into position. They all should be aligned in the same orientation. I used water pump pliers to push the magnets into the insets.
I added small holes opposite to the insets so the magnets can be easily removed by pushing them out of the insets with something like a strong needle or a paper clip.

It can fall apart and be put together again. This makes it quite indestructible.

I designed it to be printed on FDM printers with 0.4mm nozzle. If anyone needs a model with thinner mm marks just leave a comment.

My test prints where on prusa mk4 mmu3 with prusament PLA galaxy black. 

I printed with brim and organic supports everywhere with 0.2 layer height speed profile and a 0.4mm obsidian nozzle.

Grades and precision

I had to compensate for PLA shrinkage by 0.2% otherwise the ruler was off by 4mm at the 2m mark. I set this in prusaslicer for xy.

The e0 element of the 1m version should be 120.0mm and fits in my caliper for measuring and  calculating the shrinkage, without printing the full folding ruler.

If I understand the EG-Guideline 2004/22/EG (Wikipedia Gliedermaßstab) correctly my print achieved grade III, though I don't have another measure method than another folding ruler.

Similar

•  2m version with print in place hinges