We also looked at the more permanent options with better airflow and ordered a proper metal shroud (< £20 all in) but it will take a few weeks- a month to arrive:
He is right, the fan is to cool the printer head., and to make the extruded filament cool quicker. Havin the fans blow freely down are not going to work and the added inertia of the aluminium will lead to rippling on the printed surface
Dry cutting. While I use copious amounts on the lathe or mill, lubricants in the small cnc add a lot of complication. Getting it clean again to the point it doesn’t affect wood projects would be a challenge.