this is very basic,if you want precise its a trial and error or take it to techno.i start with bobbin if you don't have gauges.with bobbin in bobbin case let it hang by thread,next give a gentle down and then upwards push/pull.bobbin case should move approx. 5cm down before stopping if it go down fast and far tension is too loose,turn screw clockwise,try again.top tension I normally check by threading all the way and at tension set at 4 pull the cotton sideways and the needle should bent approx. 2-3mm before cotton pull thru.hope it make some sense
johan, August 2013
