Mini Space Invaders Carriage (Eustathios)

Description

This is a redesign of the [Space Invaders Carriage](http://www.thingiverse.com/thing:893849) for Eustathios printers. The main reason of the redesign was to make it smaller to increase usable build volume. Here's some of the changes: * smaller size, XY travel is about 290mm² (still less than the original carriage) * self-aligning bushings instead of graphite bushings (they use up less space) * 40mm extruder fan instead of a 30mm fan (less noise) * no longer supports mounting a direct drive bondtech Like the previous version, it is convertible between a bowden configuration and a direct drive configuration using a Printrbot [Gear Head extruder](http://www.thingiverse.com/thing:1052966). But, instead of switching, I opted for a flying extruder with a short bowden tube (more about that setup in [this post](http://thrinter.com/cartesian-flying-extruder/)). The hotend is mounted quite a bit higher than with the stock Eustathios build, so the bed probably won't reach the nozzle with the standard configuration (should work with the [ballscrew bed mounts](http://www.thingiverse.com/thing:854267)). **Parts:** * 2 - [5015 Radial Fans*](https://www.amazon.com/gp/product/B00PZT3YD6/ref=as_li_ss_tl?psc=1&redirect=true&ref_=oh_aui_search_detailpage&linkCode=sl1&tag=whirligh03-20&linkId=fa7c666295ca3d7b67db04d24d2069db) - link to 24V version, you may need a 12V version depending on your power supply * 4 - [5x5mm…