Happy i3v X-Carriage

***Update 1/18/2016***
I printed this carriage in PETG at 50% infill & have been using it for over a week without any problems. last night I printed a 14 hour print of a Delta Vertex. The carriage took over 5 hours to print. I included a photo of that carriage installed.

I modified this X-carriage design this past summer. I named it a happy x-carriage because it initially had a smile carved in the back plate. That design did not seem as functional as this, but it still seems happy. Thi