General MK Series:
https://www.youtube.com/watch?v=Fg9omXlYR-Q MK Series Printing Tips
https://www.youtube.com/watch?v=0Aj9WCabPgw Post Processing with a Heat Gun
https://www.youtube.com/watch?v=Llas80vYFPc Loading and Unloading Filament in the MK Series head
'MK1-250 Extruder for Standard Filaments:
https://www.youtube.com/watch?v=yaCYFmoIESk Overview
https://www.youtube.com/watch?v=v2ifSlZ0qEw Loading and Printing
MK2-250 Extruder for Flexible Filaments:
https://www.youtube.com/watch?v=SOGKeU3vLbs Overview
https://www.youtube.com/watch?v=0dS3bC0BnRQ Loading and Printing
MK1-450 Extruder for High-Temperature Filaments:
https://www.youtube.com/watch?v=UvZMecXsHEM Overview