Fan duct for Solidoodle4 w/ E3Dv6 and stock carriage

Provides a means to hold a 40x10 fan and direct cool(er) air directly around the nozzle to help reduce droops and increase overhang printing capability. I attached my E3Dv6 by removing the top lip on the E3d heatsink on a lathe at which point it slides right into the same hole the stock heater core attaches and is held with the same set screw. This fan shroud will not likely fit any other arrangement.

Since upgrading my SD4 to a Lawsy carriage (http://www.thingiverse.com/thing:104059) and stronger Y idlers (http://www.thingiverse.com/thing:731769), my original design started bumping at the edges reducing the available bed space so I made a new "low profile" (_lp) version to address these issues and recover the full print volume.

You will need to acquire four M3x20 socket head screws and four M3X8. The fan on the left of the extruder is no longer needed so is a great candidate to use in the fan shroud. It must be removed from the extruder and sandwiched between partA and partB with the M3X20 screws. The whole assembly, then, is attached to the carriage with the M3x8 screws. I printed the lower shroud (part B) in Nylon since it has a higher melting point than ABS and PLA. My settings were:

Part A ("_lp" version recommended):

material: ABS

nozzle diameter: 0.4mm

layer height: 0.2mm (built-in supports assume 0.2mm layer height - may not print well if other layer height is used)

supports: No

Part B:

material: Taulman 645

nozzle diameter: 0.4mm

layer height: 0.15mm

supports: No

After printing part A, remove any dropped loops that may interfere with the fan. You may need to drill the holes in the fan grills out with a 1/8" drill. DO NOT drill out the holes in the lower shroud (part B). Instead, tap them with a M3-0.5mm tap (chuck into a cordless drill for quick work). You may get away without pre-tapping but run the risk of splitting the part if you force the screws in.

Although the shroud does not come into contact with the extruder or heater block, I still noticed some evidence of melting due to the close proximity but the air channel remained intact. Adding a layer of kapton between the heater core and the shroud seems to help.

Unless you already have a similar fan in place, you are probably doomed to printing this twice. Once w/o the fan which should work but may not look too nice around the undercut areas and once again with the fan installed to get a cleaner print.