Added the following details:

• the spool now has filament rolled on it
• added 2 copies of a filament guide (hope one prints ok)
• redesigned the horizontal arm with steel bars
• redesigned the fan duct with shroud
• added 2 copies of the heating body with nozzle (hope one prints ok)
• main "tower" is now partly empty, added the vertical Z-axis screw
• emboss "IIIP Printer" and the tiny cube
• added filament feeder