Carriage for Delta mini MDF

Since the wood-made carriage will make noise .In order to make the printer quiet so , I design a printed-able carriage ,and the PLA carriage can get more printing space .
big one for 4 lm8UUs each side of 2 bearing .
small on for 2 lm8UUs .

this desgin is for
http://www.thingiverse.com/thing:177417
and firmware setting carriage offset is 19mm .