Chosen Solution

What direction do you turn the screw to change the blade

Robert McKinlay from the manual available here Roberts Longneck Plus Jamb Saw 10-56 (2014) - iFixit " Using the Allen® wrench , turn the blade screw clockwise until the blade clamp is tight on the shaft" To take it off, you would need to turn it counterclockwise. Righty tighty lefty loosey