YAFM (Yet Another Fan Mount) for Mk5 (and Mk6)

Here is another 50mm fan mount, this one bolts straight on to the support acrylic parts for the Mk5 (or Mk6 AFAIK) and lets you direct a blast of air directly onto the part. It is hinged, so you can swing it up and out of the way when you don't want it, with it sitting fairly neatly against the extruder body without blocking the view of the build or of the filament path through the extruder too much.