Model originally uploaded to Thingiverse at https://www.thingiverse.com/thing:4581867.
Levelling your print bed is probably one of the most important things to get right on your 3D printer. It is also one of the most common issues when you experience printing issues.
I have a CTC Replicator Dual with a 225x145mm heated bed. I'm printing on a piece of mirror that I bought from my local hardware store for $20 AUD. (The mirror was 300mm wide, by 1.2m long, and I cut the mirror up with a glass cutter).
So many times I've ran into issues with levelling the bed on this printer, as the out-of-box levelling mechanisms are a nightmare (which I plan on upgrading as soon as possible).
IMPORTANT - Disable skirt when printing this test, as the skirt WILL be printed over the top of.