My RX shutter or/and film transport mechanism shrieks! It has been suggested that it needs oiling. Should I attempt this by using modeler's oil thru the aperture gap at the bottom of the lens mount? I cannot afford a service right now but am afraid of any wear and tear to the transport mechanism... The oil I have I bought from a model shop and seems quite thin and has a long thin applicator nozzle , but I am not sure whether I should use it.. any thoughts?