Robust and precise NEMA 17 steppers / belt tensioners

I finally got rid of the very annoying and varying short belt sloppiness on my Ultimaker.

http://betterprinter.blogspot.fr/2012/11/short-belt-tensioner-for-nema-17.html

This two-piece tensioner is simple, robust and it lets you adjust the belt tension with both precision.

It also protects your case from abusive screwing/unscrewing of the stepper bolts.

Disclaimer: please make sure never to over tighten your belts as it becomes very easy to do so... It will not make your prints look b