120mm adjustable fan vent

The central hub now finishes flush with all the tolerances at 0.2mm on the hub and 0.1mm between the outer edge of the blade tips. This has essentially eliminated all of the slop. I did try 0.1mm on the hub, but it made assembly too hard.I have incorporated a small overlap in the blades and the small lip in the outer edge of the slots in the base. This closes of the air gaps and also removes the ability for the blades to be pushed through the slots in the body.I have further reduced the overall thickness (6mm down to 4.5mm) as it was still excessively thick and I didn't like the look of the shaft extending beyond the blade centre.The mount holes have been reduced to 4.5mm to take standard M4 bolts and the clearance and seating depth is designed for M4 pan head/round head bolts so that the heads sit just below flush.The ergonomics of the finger tabs has been improved by making them larger and therefore easier to use.Other minor geometry changes have been made with FDM printing in mi