Summary

This is a replacement shuttle for the FolgerTech FT5 printer. It's designed for the E3D Titan Aero extruder, so it's got nothing under the stepper motor, allowing for the max possible bed clearance. With a V6 heat block you get about 25mm space for a fan duct.

The fan duct I've included was designed to try to minimize disruption due to clips on the bed. It does lose a few mm on the X axis, but it's not too bad.

If you choose to use the part cooling fan, it was designed to fit with these fans:

https://www.amazon.com/gp/product/B00EL938E6/ref=oh_aui_detailpage_o07_s00?ie=UTF8&psc=1

The duct prints in 2 parts which have to get glued together. I use CA glue. I get a nice strong air flow out of this even without sealing the connection between fan and fan holder, though I do plan to put a bit of caulking there to fully seal it.

The order of putting things together is important:

Fan duct:
1: fan connects to fan holder
2: fan duct connects to fan holder
3: fan mount connects to fan holder

Shuttle:
1: cable chain connects to top of shuttle-back
2: shuttle back connects to rail slider
3: motor connects to shuttle back, with cable connector facing to the right (when looking at it from the front)
4: use 4 m3 bolts to connect shuttle front and back.
4a: on the left side of the shuttle, use the TOP screw hole.
4b: secure the bottom two screws with nyloc nuts. do not use nuts on the top yet!
5: attach the titan aero extruder
6: attach the fan mount assembly to the top two screws from step 4 and secure with nylocs.
7: use an m3 bolt through the bottom left hole on the shuttle to secure the bottom of the fan

I've also included an assembled STL so that you can see how it all fits together, and a bunch of pictures.

The original cad files are here: https://cad.onshape.com/documents/bdeab98e34d4910e81e0ed05/w/09297873b19d1a6b992c52fa/e/150a251ec63f9edc81ff04a8